Just regular fuzzy finding is the most common. For example, to attach a file instead of faffing around clicking in the open dialog, I type into fluent search(a frontend to everything) and it enters it in the current context i.e the open dialog.
It has a few other qualifiers, like big: huge: etc to search large files. Same way with time etc.
Rarely when you need it you prefix with regex: and you get everything you need.
It's very useful that both everything and fluent search integrate into explorer in that if you right click on the search result you get the same context menu as you would in explorer. Drag drop works, etc,. The issue with every other tool in every other OS is the lack of this feature. You basically have a virtual fully featured directory for every search result, simply cannot beat that.