Grunfeld Lines

I used to play the grunfeld some monthes ago, but i relized that i don't really know how to continue after 3...d5 and i stopped. I checked in my chessmaster opening's book and it showed really weird and uncommon lines. Can someone show me the best and the most common lines of grunfeld for black and white?

There are many lines in Grunfeld Defence, the most of all are playable.It depends of your playing style. Maybe the Grunfeld don't suits your style pretty good, so you should find other opening like King's Indian,Nimzo-Indian, etc.

I know many lines of other openings, that's not the problem. I want to learn the most simple lines of the grunfeld, because it seems very interesting, good and aggressive opening.

Perhaps your problem is that you want to learn the lines, and don't know the strategy/themes?

there are tons o lines, osmething that makes it so difficult, white has many ways he can play and black must know all of them.

In the Grunfeld you must learn many theory if you want to survive the opening stage, so you can't find simple lines.

A class player wanting to use a deeply complex and very theoretical opening is roughly equivalent to saying "I want to cut my throat, but I do not know how to do it".

You don't really have to do anything. You will succesfully cut your throat using your existing resources. Guaranteed.