I thing that he atracts objects through the force and take it with their hand (right or left). Is not his hand who controls the force, but his mind
BTW, in ESB Han fires and Vader STOPS THE BLASTS with their mechanical hand!!! 😮 😮 and then summon the force to take the weapon from han's hand (tricky phrase! i've mistaked 3 times!!!)and make it fly to their right hand.