There should be one screw on each side of the pick up. Turn it clockwise to raise it. Counterclockwise to lower it.
im asking one. the screws to the left and right of the pickup or the screws on the rings?
If its a humbucker with a pickup ring you will see a small screw on the ring dead center between the rounded ends of the pickup. These are the ones you will need, don't raise it so high that the strings hit it when fretted very high on the neck.