This should be classified as MS Windows weirdness.
I have a "file A" in a "folder A". In "folder B", I created a hardlink called "file Ah". It is clearly visible inside of "folder B". No problems so far.
Using the file search dialogue box in the upper right of the MS Windows Explorer window yields no results when searching for "file Ah". But wait, it gets better. If I then simply open and close "file Ah", then the search works.
Now, if I create "file B" in "folder A" and a hardlink called "file Bh" in "folder B", then the search only yields "file Ah". If I then attempt to proceed as before by opening and closing "file Bh", then the search does not work.
As far as I can tell, this has nothing to do with refreshing the views in MS Windows Explorer. My best guess is that an event is triggered on "folder B" the first time I open any file inside of it. But this event is not triggered in subsequent situations.