Some possibilities for reading:
50 Essential Chess Lessons by Steve Giddins
https://web.archive.org/web/20140708100833/http://www.chesscafe.com/text/review534.pdf
Chess Strategy for Kids by Thomas Engqvist
http://www.gambitbooks.com/pdfs/Chess_Strategy_for_Kids.pdf
Starting Out: Attacking Play by James Plaskett
https://web.archive.org/web/20140708101549/http://www.chesscafe.com/text/review467.pdf
Simple Chess by Michael Stean
https://web.archive.org/web/20140708104258/http://www.chesscafe.com/text/review400.pdf
Amateur's Mind by Jeremy Silman
https://web.archive.org/web/20140708094419/http://www.chesscafe.com/text/ammind.pdf
Chess Secrets: The Giants of Chess Strategy by Neil McDonald
https://web.archive.org/web/20140708092313/http://www.chesscafe.com/text/review620.pdf
Chess Strategy for Club Players by Herman Grooten
https://web.archive.org/web/20140708101926/http://www.chesscafe.com/text/review696.pdf
Chess Training for Post-beginners by Yaroslav Srokovski
https://web.archive.org/web/20140712013538/http://www.chesscafe.com/text/review945.pdf
Chess Strategy: Move by Move by Adam Hunt
https://web.archive.org/web/20140708093249/http://www.chesscafe.com/text/review890.pdf
How to Reassess Your Chess (4th ed.) by Jeremy Silman
https://web.archive.org/web/20140708095832/http://www.chesscafe.com/text/review769.pdf
Understanding Chess Middlegames by GM John Nunn
https://web.archive.org/web/20140627012322/http://www.chesscafe.com/text/hansen154.pdf
Winning Pawn Structures by GM Alexander Baburin (1998)
https://web.archive.org/web/20140718055446/http://chesscafe.com/text/wps.txt
Understanding Pawn Play in Chess by GM Drazen Marovic (2000)
https://web.archive.org/web/20140708110136/http://www.chesscafe.com/text/review249.pdf
Dynamic Pawn Play in Chess by GM Drazen Marovic (2001)
http://theweekinchess.com/john-watson-reviews/books-of-many-flavours
Winning Chess Middlegames, An Essential Guide to Pawn Structures by GM Ivan Sokolov (2009)
https://web.archive.org/web/20140708091955/http://www.chesscafe.com/text/review676.pdf
Pawn Structure Chess by GM Andrew Soltis (2013)
https://web.archive.org/web/20140708101523/http://www.chesscafe.com/text/review908.pdf
Chess Structures - A Grandmaster Guide by GM Mauricio Flores Rios (2015)
"There is also masses of stuff in the book that made me go 'Oooh!' and 'Aaah!' so I think it will have the same effect on you! In particular, I loved Rios' exposition of White's plan of exerting queenside pressure against Hedgehog systems. I'd seen one of the games he quotes in his chapter but I'd never remotely made any link to a structured way of fighting the Hedgehog structure, so this chapter was a real eye-opener for me ...
In conclusion, warmly recommended. Lots to learn!" - GM Matthew Sadler
The Power of Pawns by GM Jörg Hickl (2016)
"The didactic concept of the book is admirable. Each chapter defines the structures, explains the typical characteristics and shows the plans for both White and Black. The reader participates by assessing positions and invariably receives useful tips for practical play." - FM Harry Schaack
Python Strategy by Tigran Petrosian
http://sagarteacheschess.blogspot.com/2015/09/python-strategy-book-review.html
Petrosian’s Legacy by Tigran Petrosian (1990)
https://web.archive.org/web/20140708103409/http://www.chesscafe.com/text/review309.pdf
Petrosian: Move by Move by
Hello,
I've been stagnating around 1600 for quite a while. The problem is that I do not know which part of my chess I should develop more. It is certainly not tactics since my rating of chess.com tactics is 250 more than my live chess and neither do I think it is endgame, which I think is a strength and I don't lose much in the endgame, just in the middle game and sometimes in the opening. Please help.
Also please provide tips to develop that specific area you mention.
Thanks.