Best way to learn endgames with Rooks and many pawns?

I struggle in many endgames and find myself losing many rook endgames even when I am up a pawn and there are 5-10 pawns total. I already know about some of the theoretical endgames like Lucena and Philidor positions, but I have trouble when there are many more pawns on the board. I was wondering if anyone knows of any intermediate-level books/videos that go over typical strategies in the earlier stages of rook endgames, rather than just the theoretical/database endgames with very few pieces (like the Silman endgame book).

I'm hovering around 1800 elo on lichess btw.

Good topic. I am interested as well. 

I couldn't read it yet but did you checked Endgame Strategy?