There are utilities out there to convert pgn to polyglot (bin).
SCID vs PC

I couldn't tell you why the polyglot books (.bin) were chosen.
A Google Search for "chess polyglot books" or something similar should turn up enough responses to keep you busy all day. Here's one such link. Click the download links to download all of these books.
I've always searched databases (of games) not seached opening books (as your response above seems to indicate). You don't need any books to search for chess databases. Can you open a database and search for just certain games, as described above?
im trying to search for games in a database with specific openings.
im searching for openings that I have regularly played but they are not coming up in the searches.the only time anything comes up in the searches is when i select the entire opening range from the ECO button(A00-E99)
the ECO button in the search function only lists 59 openings.
i presume the ECO button is related to the opening books installed.

Try this:
Load your database.
Click EDIT and then SETUP BOARD.
Set up an early, opening position that you know is in this database. Click OK when done.
Click SEARCH and then CURRENT BOARD.
Leave the different search types at their defaults. (Exact position, reset filter)
Click SEARCH.
I followed these steps with a database of my own games, and successfully pulled up every game where I played 1.g4... the Grob.
Ive tried that and it doesnt work either. maybe i need to reinstall.
Can you tell me what the ECO range is in your search function.

Regarding the steps in post #329, the ECO range never comes into play. When searching for a position this way, the ECO range is irrelevant and doesn't show up on any screen.
Regarding the steps in post #324, as I mentioned, I specifically chose B10-B19 for that particular example search.
By default, unless it gets changed, the ECO Code is A00-E99.
Ah, wait a minute... I just figured out your problem.
I'll bet it's because your database (a PGN file?) doesn't contain any ECO tags. It appears as if Scid vs. PC doesn't figure out each ECO code on its own, but just looks for the tag. If you're searching for ECO Codes, you must have this tag in your pgn header.
I say this because when I asked it to bring up all of the 1.Nf3 games in my database, it didn't find any, which I knew was wrong.
But still, you should be able to search via the steps in #329.
Thanks Ed. i dont have ECO tags in my Pgn header but when I search by your method it doesnt return result.
I play Italian game mostly so there should be many games with this opening but it doesnt return any.
BTW how do i edit ECO tags in header. do i need to create a text file and then edit it with ECO tags and then convert it back to Pgn

The only method I know of to add an ECO tag to the PGN header data would be to add it by hand, with any text editor. I've never heard of a utility that will (a) read an exiting PGN file that didn't have this tag, (b) determine the ECO code needed, and (c) add it to the file, automatically.
If your pgn file only contains a couple of dozen or so games, this (doing it by hand) won't be a big problem. But if the file contains many games, (hundreds or thousands) then that's a lot of work.
But I still don't understand why you can't search your database by first setting up an opening position and then SEARCH and then CURRENT BOARD. You must be doing something wrong, but I don't know what.
ive just tried again and it worked. thanks Ed. thats been a great help.
thanks also to whoever is involved with Scid. Ive just annotated my first games and its great to be able to view the numerous possible variations. its a great complement to any chess book.
the only fault i can see so far is that Scid cant find openings without ECO headers and why is the ECO range so limited.
thanks again
btw is there anyway i can save a board setup position to use for regular searches rather than having to manually set up the board each time

No problem.
Re: Saving a board setup: There's a couple of things you could do.
(1) After setting up your board position, and then leaving that window, click EDIT and then COPY FEN.
Now paste the FEN into a notes.txt file.
Example:
Notes: The following FEN is 3 moves into the Ruy Lopez:
r1bqkbnr/1ppp1ppp/p1n5/1B2p3/4P3/5N2/PPPP1PPP/RNBQK2R w KQkq - 0 1
Next time, you don't even have to go into the EDIT - SETUP BOARD window at all. Simply open your notes.txt file, copy the FEN you saved, and then click EDIT and then PASTE FEN.
(2) Alternately, if you're always filtering a database into a smaller database of just a specific opening, and doing this repeatedly, then once you do it the first time, then SAVE that database of just those filtered games. Then you never have to set up a filter to achieve it in the future... you can just load this smaller database directly.
For example:
Load your large database.
Click EDIT - SETUP BOARD, and then set up the opening position you want, as we've talked about before. Click OK.
Click SEARCH - CURRENT BOARD.
After the games have been filtered of jusst this position, click TOOLS - EXPORT ALL FILTER GAMES - EXPORT FILTER TO PGN and save these games into their own pgn file. Call it something appropriate, such as My Ruy Lopez Games.pgn, for example.
Lads how do you copy all games in a games list to the clipbase.
Ive pressed Ctrl+A to highlight the whole list and then copied it to the clipbase but it only copied one game over even though all were highlighted.
Im trying to get all my chess.com games in one database

Right, it should be at the bottom of the gamelist window in SCID vs. PC so you shouldn't have to open anything else. It looks like this: Red arrow shows what you should drag.

Lads how do you copy all games in a games list to the clipbase.
Im trying to get all my chess.com games in one database
By now you've noticed you can have more than one database open at the same time. (I don't know what the limit is but it's probably a lot.)
Once you've opened all of your databases, pull up your game list window. You'll see a tiny icon of each database at the bottom, along with an (empty) clipbase icon.
Just drag.
Grab each of the databases and drag it TO the clipbase. Once you do you'll see the number of games in the clipbase increase.
Once you're done, you can save this clipbase.
Alternatively, if all of your games are in a pgn format, and in the same folder, just use the old DOS copy command.
copy *.pgn all.pgn
This will copy all pgn files in the folder and merge them into a single pgn file, called all.pgn.
Thanks for reply.
The 40000 position opening book above is a .sbk extension
why is it in this format if scid requires .bin extension.
Regarding the search function
I think Im doing the searches correctly but the opening book that comes with Scid is very limited so i think thats why it returns zero results.
So far the only drawback i see with Scid vs pc is the opening book. I would imagine thats an easy thing to fix with a few book downloads but i cant find opening books with .bin extensions