Smart Collection returning more than I expect

Hi, all

It is all about restricting a smart collection filter to a particular LR top folder.

Say I have 2 top LR folders D:\pictures and D:\videos.

I want the query to get the items from D:\pictures only.

Folder Contains "pictures" will return them all but will also include any LR folder with "pictures" in it, e.g. a video in the D:\videos folder called "videos showing my pictures of the holidays". That is normal.

So I changed the smart collection to Starts with "pictures" and Ends with "pictures". That is unique but it still returns the same. I made sure to use the "All conditions" options which I assume is equivalent to an AND.

I tried using Contains "D:\pictures" ,and other similar attempts, but none of them find anything at all.

I resorted to assign keywords like "Dpicturesfolder" for the whole D:\pictures but that is not "smart" as I have to make sure it is always up to date.

I could change all occurences of "pictures" and refrain using it in the future but that is not smart either: I have many of those top folders with commonly used words like Documents, Music, Events, Travel etc. for example and I cannot go round telling people not to send me pictures sets with these words in folders.

I could make a collection of the top LR folder with a unique name but that has the same drawback at the keyword solution (it needs to be kept up to date).

I could also resort to rename D:\pictures to "D:\top folder pictures" or something else unique but where will it end to sort out what seems like a bug or a misunderstanding of mine.

I  might be missing something here but in that case, I still need help.

Kind regards

Bernard