can somebody explain thre difference between shuffle and random (i'm speaking russian natively)

Well, I'll go ahead and tell you that foobar does not shuffle. The "shuffle" option is actually random.

Strictly speaking, shuffling songs means that you take the songs, and play them randomly, but only once. It should be just like shuffling a deck of cards. You pick one, then you pick another, then you pick another, etc, but you you never pick the same one twice.

Random means that you pick completely at random. You can repeat songs with random play.