Hi Maks. Firsty your reverse serve action looks great, very impressive! To get it short all the time I think you need to focus on the first bounce on your side and where it is landing and getting it consistent. So aiming for about halfway up your side of the table will get 2 bounces on the opponents side, if you can also get a slightly softer contact on the ball.
So when you practice again try to focus on the same technique but a lighter brush on the ball and getting your first bounce consistent. If you can do that I think you will have a really nice serve and be able to keep it short all the time, keep up the good work!
