As someone with one of those very strange brains that remembers things oddly, I can explain my typical process of recollection.
It's a bit like random firing, a vast sea of facts that can't be sifted through, and you lock into a particular subject and things just start coming up. Actually visualizing what someone or something looks like is like trying to focus on a spot in my vision, it slides away as soon as you do.
If you're trying to recall the name of someone you met a month ago, it's all but impossible. Your chances of ever recalling their name will depend on how many ways you can come up with it, did you play pool together, do they have the same name as someone else you're familiar with, do they look like someone else. Every detail that sticks out will help, because when you're trying to figure out their name, those details are what you have to actually think about.
When you're trying to recall something larger that fits together, like the way a command economy works versus a market economy, or the plot of a book, you dip into that general area and grab hold of one little bit of information. From there it spreads like a virus and pretty soon you've got the entire subject mapped out, with extraneous thoughts that are only somewhat relational to the subject firing off throughout.
Dates, names, things that are arbitrary, disconnected from the overall fabric of what something is, are like using a sieve. They just wont come. I can recall playing pool in college, and remember a staggering depth of detail about the people I played with, details about individual games, individual shots in those games, personality quirks, people that were simply present often are recalled in vivid detail, but I can just barely picture them at all when it comes to physical attributes like eye or hair color. I remember basically everything I knew about them, but I would struggle to describe what they looked like because it's not part of who they are, and I remember not a single name of any of the dozens of people I could easily map out well enough for them to recognize each other, just because I thought about playing pool. What makes a thing the way it is, relational material that ties together into something larger, is very easy to pull up, but it comes up like a brainstorm would from a very large group of people.
If I want to remember the name of an actor, say Bruce Willis(yes, I forget his name frequently), I often end up recalling the names of many movies, people he acted with, movies they did that he wasn't in, and some times it can be hours before it pops up while I'm doing something else. I can only tell you there are 12 windows in my house because I know there are two per room, that one bathroom and the kitchen sink have one, that the dining room has a beveled corner for three, and I realized I was wrong and that there are 13 while adding them up, because the living room has two, but I was thinking of the big living room window I had as a kid. I actually forgot how many windows are in my own living room and had to go look...
Not the best example of good recollection.