Here is one example, a most simple search
Most definitely the are video files under that path, but Opus finds just nothing. I think, the search is maybe the weakest part of the program (sorry, & Opus is nevertheless by far unmatched!), & i never liked the search. For example, i set a path like K:, but Opus will still search all drives, but not even finds a single video file, no matter, if i chose the path from the searches dropdown menu, or, like in the image, in the search definitions.
Please show us some of the files you think should be matched but aren't.
Sure.
Any idea?
The simple filter contains location & name, not quite sure, if i'm using it right, though.
None of those files will match Path = K:\Bilder\Fotografie. They are all in sub-folders.
You can use Full Path = K:\Bilder\Fotografie\* (with Use Wildcards on, of course) if you want to restrict the results to just files in or below that folder.
But you could also remove the Path clause entirely, and remove the first K:\Bilder line from your Find In list, so you are only searching below K:\Bilder\Fotografie. If you're only searching in that folder, then you don't need to add an extra clause to restrict the matches to a particular folder.
Alternatively, you could do the entire search from Simple mode, since the Name wildcard can be applied there and you don't really need the Path (or Full Path) clause if you just want to look for things in or below one folder.
Everything works fine, you just need to think a bit more about what you're doing.
Oh, ok, i see. I got to test in the afternoon, just came back late. Thanks you. 
Everything works fine, you just need to think a bit more about what you're doing.
Yes, sure. I didn't think, this could have possibly been a bug. Maybe i should play around with the search more often, because the filters thing surely is very powerful. 
Sorry, no success. By the way, i have tried K:\Bilder\Fotografie * already. There are definitely dozens of video files somewhere under those folders, but yet nothing is found.
The same happens with the simple search, using *.(avi|mpeg|mov|mpg).
Edit:
K:\Bilder\Fotografie[Backslash]*
The editor refuses to show the last backslash for some unknown reason, so it's not a typo.
Simply double it or put the expression into back ticks
K:\Bilder\Fotografie\*
K:\Bilder\Fotografie\*
You're using Path not Full Path. Please read my reply above carefully.
The post editor has a link to forum tips above it which should help with backslashes. Worth a refresher if you haven't read it in a while.
Leo, sorry for my mistake, but i think i have found the problem now. In the indexing options, the file types in question (the video ones) were all missing. 
I'm re-indexing now. I have no idea, when or why i might have excluded those file types. Maybe because of some issues with a CPU hogging indexer interfering every once in a while, from the early days of Windows 10, & must have forgotten it? Not sure, since this a few years ago. Anyway, i guess, this has to be the reason, naturally.
File Types won't make any difference if you're searching by extensions. That's just a wildcard tested against the filenames, neither of which are affected by File Types.
The reason it isn't matching anything is as I said above, I think.
When i use the full path, i still get no results.
You can use Full Path =
K:\Bilder\Fotografie\*(with Use Wildcards on, of course) if you want to restrict the results to just files in or below that folder.
That's what i tried. All files in question lie in a subfolder "Original" below "Fotografie", so they'd have to show up. Very strange.
Screenshot please.
Do you have any *.(avi|mpeg|mov|mpg) files in or below that path?
Looking again at the screenshots above, I only see .jpg files.
Yes, of course i do. Those folders contain images from digital cameras, mostly JPGs. On rather rare occasions i shoot some short videos, which are under one of the sub-folders. Since i'm using more than half a dozen camera brands, the video formats can be different. You can see in the first image, that there should be at least one .MOV file (there are a few more, scattered inside almost 1000 folders, which was the reason in the first place, to use the filtered search. I'd like to copy them over to a separate folder to have a better overview).
I have some date stamp folders, which only contain the JPGs, plus one .GPX file. below that, i have the "outtakes" folder, one folder holding the original files (unprocessed), and in some cases a leftover Lightroom folder, which may contain stuff. The vids used to be in the "Original" folders.
Ah yes, I missed the mov at the top as it looked like a folder to me (at the top and a different, blue color).
I created a similar scenario (E:\ instead of K:\ is the only real difference, I think), and it's working OK here:
Edit to add:
Make sure you are not filtering the results, either.
The status bar doesn't seem to be turned on, or is cropped out of the screenshots, so we can't see if anything is being filtered out. If in doubt, try the Show Everything command, which is in the Folder menu by default (Set SHOWEVERYTHING=Toggle).
Ok, the files were hidden 
, indeed, that was a very good idea. I have missed that completely. But i have no idea, why those files ended up hidden. There is no active filter running, as far as i know. I have to check the custom folder settings later. Thanks!
