Hey man
dont take this the wrong way, but that isnt jazz at all.... neither is playing penatonic phrases over a jazzy backing track considered jazz.
I'm only saying this because your title states "how to improvise on jazz playing"...
that being said in terms of tips, i think you can try and target the changes of the backing track ie figure out the chords for the backing track if its not provided and learn the different scales/arppegios over the chords.
for a simple way of making yourself sound more sophisticated: play the minor pentatonic scale one whole step away from what you were doing in the video ie play Bm pentatonic over Am, this creates the dorian mode sound