Manage Library- how do I turn off "require exact matches"?

[towers of silence]

I'm trying to replace some missing media files in my library and a couple of the options that should be available under the "automatic search" menu don't seem to be there- specifically, when I unfold the triangle by the automatic search option I can set a specific folder to search and I can enable or disable the options to search project and search library but I want to turn off the option to "require exact matches" and that doesn't show up for me. Is this option found somewhere else? It's not in the preferences menu either...