Document registry, but I've heard users doing this in just about every application that allows it - just doing a broad search and memorising the page that the thing they actually want is on
Was about to say, either doc registry, or library catalog.
That's the neat thing about consistent search indexing that isn't being maliciously subverted or tweaked. Once a "good enough" structure is achieved, genearally someone can quickly find their way around. I call it the Librarian effect. I first grokked it's impact when I'd volunter to reshelve books in the library. Given a relatively ordered cart of books to put back on shelves, and an arbitrary starting point in the library to begin restacking (imagine going to the bathroom and some student comes and moves your cart on you), once you've done it a few times, you can usually unconsciously navigate the entire data store.
Compare this to most Search Engines, Reddit, or most Internet forums, where you have people maliciously attacking your overall index structure in a constant conflict for top page rank, orconstantly shifting page numbers based on time elapsed since last reply/engagement sorts.
Swear to God, might one day make a Dewey Decimal System-like search Engine. I've not encountered any other way of organizing information that seems intuitively mappable quite like it. Though I'll admit, I'm not sure what gives it the "stickyness" for me, the numbers, or the physical location. I'll preferentially choose a library whose physical layout I'm familiar with over one I don't, but if you take that physical layout and switch around all the numbers, I'll find you, and beat you with the heaviest reference volume in the Library once I find it.
Seriously though, even if you throw me in an unfamiliar layout, I'll generally quickly refresh on general identifiers then do a quick jog through the Library to nail down the layout. Haven't done many non-Dewey libraries, and hate the ones set up like bookstores where you don't have interleaved levels of sorting.
What on Earth is your application where that's the case? ..A forum maybe? (Revisiting a thread looking for a particular reply I mean.)