Ive been doing something similar recently and I think the general advice is usually, think of a topic you're interested in and look for 'good' books in that topic.

That being said here is a couple of books I picked kind of randomly because I liked the sound of them Into Thin Air: A Personal Account Of The Everest Disaster - Jon Krakauer Spying on Whales: The Past, Present, and Future of Earth's Most Awesome Creatures - Nick Pyenson What We Owe the Future - William MacAskill