Of all the chess books I've read, I think the one I am benefiting from the most
is,
"The Art of The Middle Game"
by Alexander Kotov and Paul Keres.
I say benefiting because I am still in the middle of the book. But so far it has answered and continues to answer my questions. Looking at a position, I can now tell what move not to make, which is half the battle. All I have to look for is the best move of all the playable moves. I recommend it highly. Of course, I have to get
Aron Nimzowitsch's My System
because Foygel says so.