I've noticed after I've switched to audiobooks that my retention is horrible compared to reading. For actual complex topics, it's even worse.
I would like to learn to focus... (https://youtu.be/1IRn8BN3Qhw?t=331)
I used read a lot of books when I was younger, then slowly stopped, and found getting back to reading quite hard as well. Armed with the knowledge that I used to be able to do this, I just forced myself to. And after a while, I found I had no trouble committing any more.