Thanks for the "name:shop" tip. I did set the Finder Setting to 'Search the Current Folder' quite some time ago–that setting is very helpful.
Since we're discussing search scope, there is a behavior I find contradictory.
When, for example, in Numbers.app, I do a File > Open, the top dropdown menu lists the current (most recently used by Numbers, I believe) folder, as expected, but when I enter search criteria, "Searching "This Mac"" is shown in the dropdown menu; not my current folder. However, the highlighted tab is set to the most recently opened folder (from Numbers), e.g., "Bob's budget stuff" (which is indeed, my 'current folder'). No results are returned, because the scope is set to that folder; not to "This Mac", as displayed in the dropdown menu:

If I then select the *tab* "This Mac", I get "shop" results returned:

Since "Searching "This Mac"" is displayed in the drop down menu (and is positioned directly left of the search field, to boot), I would expect (but not want) the scope to be "This Mac". This example is not in the Finder app, but I think the search behavior is comes from Finder / search.
My current folder is the active folder in the search row (with folder tabs listed), and in agreement with my Finder preference; that's all good. I do understand that the "Search: This Mac Bob's budget stuff 'row' has a plus sign button where you can select filters, and that can be useful, but the dropdown scope should follow my Finder preference (which is indeed the highlighted, and in scope, folder, on the 'Search' row, IMO.
I reported this to the Apple feedback site.