Please fix the fouling

Please fix what is a foul and what isn't. Defenders continually pulling the shirt back when a player is through, this happens 3 or 4 times. Players tripping over players. Tackling from behind and wiping out our player. None of these are deemed a foul. Yet my player running in front of theirs and taking the ball off them without touching any player and their player running into my player who has the ball is deemed a foul. I've even had it where my 2 defenders have hit each other and they opposition gets a penalty. Please fix this. It's so bad theirs no point in having a ref.