What are your methods for retaining read information?
I've watched people read technical books quickly, reading as if they are novels. The net result is that they haven't internalised any of it, just gained an awareness.
Sometimes that's all you need to do, to become aware of things, but sometimes you need to engage the material in hand-to-hand combat.
“Tell me and I forget,
teach me and I may remember,
involve me and I learn.”
― Benjamin Franklin
Get involved.Once you've got the hang of this expand it to pages and then chapters.
Get someone else to test you a short time (a few minutes) after you've read the chapter. Get them to test you a couple of hours later. Get them to test you a day later.
Teach the concepts to someone else.
Implement them - learn by doing.
But when it comes to fiction, I can finish a book, wait a week or so, then read it again and only have a rough idea of the general plot in my mind. It's like all details are flushed within days. If it happened with nonfiction or other learning I'd work on strategies to improve this, but as it is I kind of think of it as a benefit! I get to experience my favorite books (and movies) afresh many many times and never get bored.
I am always amazed how little people write during lectures, meeting and when reviewing documents.
Even easy concepts noted help create a chronological memory jog.
You say you are having trouble retaining details, how fine grained are we talking about? Because you WILL forget some details, it's unavoidable.
it's quite experimental at the moment