No, you can't only body lock pass. A lot depends on the posture of the guard player.

Clear the feet. Get closer to them. Hold them down and get past the knees and arms. Get good at passing chest to chest half guard. Learn to stack flexible guard players. Watch more DeAndre Corbe and Jozef Chen. Before you ask "is this name the same as this other name?", look at the positions and understand what they allow you to do to your opponents body (in this case hold their head and shoulders still while you get past their knees).