Well, I got pretty far. I think I unlocked 3 or 4 new maps before giving up.
Something to do with magicians, religion, and a couple others. At first, I tried hard to think of what fit. I then started doing random guesses of anything I could think of. After I got stuck, I realized that some connections are far off the point... but also related.
For instance, the connection between "on the farm" and "magicians" is "BS". Where did that come from?