On Vol 5 . . . The WWW search programs seem to gather up all kinds of vaguely associated articles and files. This is no carefully pointed search process.
Serendipity is in full control.
This is more fanciful and intuitive than more formal Boolean searches because the search engines are more sloppy and forgiving. They collect too much and give you a list of vaguely associated items. This is both a hindrance and a blessing. Free association spawns creation but can rapidly drown the thinker in irrelevance. For more on this topic . . .