Site the neck by looking down the bass while holding the body, pointing the neck away from you. If it's bowed, you probably need to adjust the truss rod. If not, then raise the action.
The moving back and forth is intonation, not action. Most bridges use small hex screws to raise and lower the saddles.
Like so:
that's a guitar, but same idea. The screws move up and down with a tiny allen key, usually 2 per saddle.