user7534: Which book is better for a 1700-1800 player? 

Pawn Power in Chess by Hans Kmoch (originally Die Kunst der Bauernführung, 1956)
Pawn Structure Chess by Andrew Soltis
Chess Structures: A Grandmaster Guide by Mauricio Flores Rios, or 
The Power Of Pawns by Jörg Hickl.


user8160: If you are talking about strategy and positional play (pawn structures included) why don't you try one or both of

Aron Nimzowitsch. My System (originally in German: Mein System), 1925,
Mark Dvoretsky. Strategic Play. School of Excellence: 3. Olms, 2002, 3rd ed 2008. ISBN 978-3-283-00418-7

These books have been tested by time. The best chess players were reading them when they were at your level.
Moreover, it's better to start with 'classic' materials and then move to something that truly suits your taste, like maybe one of those books you mentioned. 

user912: I would take a look at The Art of the Middle Game by Keres and Kotov. It is the only book I know of which devotes serious attention to pawn structure in a way that goes beyond opening development.
If you liked My System you might also check out Chess Praxis (also by Nimzowitch). It isn't on pawn structure specifically, but details Nimzowitch's theory of Prophylaxis, covering pawn structure in the process of doing so. It's a good follow up to My System.
As to the books in your question I've heard great things about Pawn Power in Chess, but haven't read it myself so can only report second hand.

7534: <p>Which book is better for a 1700-1800 player? </p>

<ul>
<li><em>Pawn Power in Chess</em> by Hans Kmoch (originally <em>Die Kunst der Bauernführung</em>, 1956)</li>
<li><em>Pawn Structure Chess</em> by Andrew Soltis</li>
<li><em>Chess Structures: A Grandmaster Guide</em> by Mauricio Flores Rios, or </li>
<li><em>The Power Of Pawns</em> by Jörg Hickl.</li>
</ul>
 8160: <p>If you are talking about strategy and positional play (pawn structures included) why don't you try one or both of</p>

<ul>
<li>Aron Nimzowitsch. <a href="https://en.wikipedia.org/wiki/My_System" rel="nofollow noreferrer"><em>My System</em></a> (originally in German: <em>Mein System</em>), 1925,</li>
<li>Mark Dvoretsky. <em>Strategic Play</em>. School of Excellence: 3. Olms, 2002, 3rd ed 2008. ISBN 978-3-283-00418-7</li>
</ul>

<p>These books have been tested by time. The best chess players were reading them when they were at your level.</p>

<p>Moreover, it's better to start with 'classic' materials and then move to something that truly suits your taste, like maybe one of those books you mentioned. </p>
 912: <p>I would take a look at <a href="https://books.google.com/books/about/The_Art_of_the_Middle_Game.html?id=qyzDAgAAQBAJ&amp;hl=en" rel="noreferrer"><em>The Art of the Middle Game</em> by Keres and Kotov</a>. It is the only book I know of which devotes serious attention to pawn structure in a way that goes beyond opening development.</p>

<p>If you liked <em>My System</em> you might also check out <em>Chess Praxis</em> (also by Nimzowitch). It isn't on pawn structure specifically, but details Nimzowitch's theory of Prophylaxis, covering pawn structure in the process of doing so. It's a good follow up to <em>My System</em>.</p>

<p>As to the books in your question I've heard great things about <em>Pawn Power in Chess</em>, but haven't read it myself so can only report second hand.</p>
