Is there a natural way to unclog my drains?

I have used a plunger, and bleach, and I would rather not go out and get a chemical draining fluid because thats even more chemicals and exspensive. Is there another way i can unclog my drains? They are all making noises when one is clogged or being used, which means they must all connect in my tiny apartment and the clog is in the middle of the drain.