In Windows 7, when I would click the Start button and then start typing a search term, it would start displaying the corresponding search results.
On my 2 Windows 10 machines that were upgraded, it will only show results from items in my Documents folder, Desktop, etc but not items in my Dropbox which is at c:\Dropbox even though I added it to the search index and the computer has finished indexing.
I know the files are in the search index because if I click "Search My Stuff" it will then show the correct results including the items in the Dropbox folder.
It isn't a big deal but it is a little annoying having to go an extra step every time I search for a document.
I get the same behavior when clicking the Search/Cortana icon also. Any ideas? Does it only include items there that are in your Users/username directory?