It can't. I have a Super User post [1] that describes the problem in detail. Windows Search and Cortana appear to be two separate things. If what I describe in my post is working on your computer, we should talk... I need to find a solution to this issue and Microsoft Support couldn't help.
Can you tell me - do you have Cortana's voice stuff enabled? Do you have her "learning" about you enabled in settings? Did you upgrade to W10 or do a fresh install?
I'm running the Anniversary Update. Maybe things got better. It also sounds like you might need to rebuild your search index and make sure all the folders you want to be searchable are indexed.
Yeah... I did that, and sfc /scannow, which was also recommended. All the necessary directories are fully indexed. If the Anniversary Update fixes it I'll be a happy camper.
I'm not affiliated with it but Agent Ransack just does search the old fashioned way, but fast. Sear inside files works properly too, without waiting for some sort of index that may, or may not be complete.
I use the command WIN + q which launches the Windows "Search the web and Windows" menu/dialog which I can type a local file name or installed application and quickly open items.
Can you tell me - do you have Cortana's voice stuff enabled? Do you have her "learning" about you enabled in settings? Did you upgrade to W10 or do a fresh install?
[1] http://superuser.com/questions/1105529/cant-search-folders-o...