Having a higher quality set of players does not mean you are the better one. The game is a combination of players, tactics and formation. Also a bit of luck from the result generator. Having a 5 star player does not mean tht player will score in every game, or block every shot.

At this point you can jst browse the forum and find the answers you are looking for. There is no black and white (straightforward answer). Do some homework by reading the various posts in this forum. You may want to replicate some tactics used by the more senior players here in the team showcase forum.