I inadvertently had omitted a space after a colon for one of my collection names. When searching for the collection, the missing space affects it from showing up in the results.
Here's a contrived example:


I'd expect the "Collection" part of "Bug:Collection" to be treated as a separate word.
Instead, the entire name is treated as a single word:

8.3 SR-3 (8.3.0.0034) on macOS 10.14.4 (18E226)