Hi psionl0
The literal, concrete, physical meaning of "nothing" or "no X".
There is how it works, take a room, floor, walls, roof and a door. In that room is nothing else in there than air, dust and so on. But there is something else, everything else that could possible be there, is there in the following sense: If there is no chair, then physical there is a physical presence of no chair. No chair; i.e. the combination of no and chair, is physically combined to the presence of an actual, literal and physical present no chair. Everything else that is not there, is physical there as non-X.
An instrument which measures air in the room, also measures the actual, literal and physical present no chair.
That is how there is no chair in the room works, there is an actual, literal and physical present no chair.
I see no chair means I actually see the actual, literal and physical present no chair.
The other explanation is that "no chair" is in fact something else, I see no chair, because I see through air and see the walls and so on.
"Doesn't exist" is not literally, physically and actually "doesn't exist", it is in the literally, physically and actually sense always something else.
Now this rule only applies within the universe, because seeing takes place inside the universe and what is outside is unknown. Not "doesn't exist" in literally, physically and actually sense.
So that is the connection between I don't see X and there is no X. What I know of the universe, requires me in the universe and that I know requires me. I can only know of that, which I can know and I can't know nothing about outside the universe, but that doesn't mean that there is nothing outside the universe. It means it is unknown.