Which phase of the game do you want to improve in ?
can anyone help me

most likely the ending part becayse i can manage with opening but i am a kind of player who finishes his game in middle only There are rare chance of a ending equal postion plzz

About the endgame there are really great books !! I am reading some chapters of " Essential Chess Endings: The Tournament Player's Guide" and I find it a really nice book for our level !

The ePlus reader is good (http://eplusbooks.com/), and I think is also being used now in New in Chess books. Gambit Chess Studio (see the recent review at the ChessBase site) is the new bomb in my option but is only available so far for the iPad. The Everyman Chess Reader is also pretty good and lets you import PGN files (and their books are in PGN format). These all let you view the text and board on your screen. I've seen some top class endgame and other books from these companies and have used their readers with pleasure. (Everyman's reader does not display text and board on the same screen on a small screen, at least not on the iPhone, but does on the iPad.)
Kindle has many ebooks available but doesn't have a reader that displays the board.
I just realized that there is also a SmartChess reader that someone recommended in another thread. I just got it but haven't evaluated... I'd searched all over for a My System ebook and they evidently have it.
do you know a very good e chess book for intermidiate chess player.If any one knows so please tell me
'Tx