Searching for hard sci-fi that hooks me—any recommendations?

I’m a huge sci-fi fan, but I’ve been struggling to find books that really hook me. When I read, I need my sci-fi to be at least mostly hard—some hand-waving is fine, but if it leans too much into the fantastical, I just can’t stay engaged.

For reference, I loved The Expanse, The Martian, Project Hail Mary, Children of Time, and the Pandora’s Star series. Those books completely pulled me in, and I never had a problem staying interested.

Right now, though, I’m on the second chapter of Hamilton’s The Dreaming Void, and I am struggling. I read a bit, and my mind starts wandering or I get sleepy. I don’t know exactly why this happens with some books but not others, but I definitely need a certain kind of sci-fi to stay engaged.

So, does anyone have recommendations for books that might click with me? I just started a new job with a ton of free time, so I could really use some solid reads.