I wouldn't say that the move 7. cxd5 wins. It gives White the advantage, certainly, because the natural reply 7. ... cxd5 can be met by 8. Bxb8 threatening to win White's Queen with 9. Bb5+. So Black would have to recapture on b8 with his Queen and lose the possibility of castling.
In the generalized position with White Pawns on c4 and d4 facing Black Pawns on d5 and c6, the move c5 (by White) is typically a mistake because it releases the tension in the center and allows Black to play for the strong break e7-e5.
Hi. Need a bit help with explanation on this position. I often end up with similar positions while playing as White where I play simply c5 and my idea remains to restrict the activity of Black's dark square bishop, keeping eye on the center and with some follow up moves like Nd2 and b4 my queenside looks good to me. But engine analysis recognizes this as mistake of not taking proper advantage of Black's weakness. I want to understand what was Black's weakness as Black just played Ne4 and how cxd5 is beneficial for me in long or short run for the rest of the game.
Any suggestion on which positions to study for clearing similar concepts and how to take good use of these small advantages will be very helpful and appreciated.