Fluff time: how powerful is the Force really?

Anyone who has viewed the Star Wars franchise of movies (warning, there might be spoilers in this thread) have seen many attributes of the Force. Such as you can use the Force to control people’s minds, to make them agree with you, you can create noise to distract someone as Obi Wan did on the Death Star, use it to shoot precisely as Luke did when he destroyed the Death Star, use it to pick up items as Luke did his light saber when the snow beast was about to make a snack of him, Yoda used the Force to raise an X-wing fighter sunk in a bog, and Darth Vader used it to pummel Luke with debris to knock him into the carbon freeze unit and even use the force to flick the switch. If the Force is powerful to do all of that, why is it not powerful enough to work on people? I mean, if Darth Vader was powerful enough with the Force why not just use it to drop Luke in the carbon freeze, hit the switch via the Force and voila, frozen Luke ready to deliver to the Emperor . Why could not Qui-gon Jin use the Force to take Darth Mal’s light saber pugil stick from him? For all the Force seems to do, it seems to be powerless against use on a human less the few times Darth Vader choked people with it.