The Translated Russian 'Secret Book Of Alien Races A.R.B" 2016 HD

All those different races would explain all the different types of UFO's seen all over the world.

There is something strange about it though, I can imagine 1 race choosing to hide itself from humanity.
Maybe 2 or 3 even, but it is all of them. They all make effort to stay hidden, or perhaps we just can't see them.
This is what binds the whole UFO phenomena, as if they all operate from the same source or by the same laws.

Why is there not 1 race just exposing themselves as if they don't care?

And if we can't see them, cause they are in a different dimension or something, how come all of them can see us?
There has to be 1 of those races unable to see this dimension, and show up as if we humans don't exist.