well the scenes would have to be good wouldnt they?
because what if they show scenes that are boring/bad, then people would say ''bad job you have been doing''
It's really not at all supposed to convey scenes of any discernible nature at all.
A teaser trailer is literally just to tease at the theme/atmosphere of the product.
This is teasing at the atmosphere of Star Wars.
It has a spaceship, it has a speeder, it has storm troopers, it has a desert planet, it has a robot, it has a lightsaber.
These are all things related to Star Wars, and the trailer is teasing at them. It's not trying to sell the plot or cast of the movie, or it's comedy or action.