(imported comment written by SystemAdmin)
I think the first thing to do would be to write relevance that properly determines what the name of the documents folder would be. From there, it’s simply something like…
exists folder “Documents” whose (exists folders of it) of folders of folder “C:\documents and settings”
However, keep in mind that not every OS uses “documents and settings”, the profiles folder doesn’t have to be on C:\ and the “My documents” folder doesn’t have to be called “Documents” - though probably it is.
So now that I confused you… Unless you’re targeting a specific OS, I’d start dealing with using:
csidl folder 46
which points to where the common documents are located. The last folder in
following text of last “” of pathname of csidl folder 46
shows how the “documents” folder is named on the PC.
parent folder of parent folder of csidl folder 46
shows where the profile is located on the PC
So how about something like…
exists folder (following text of last “” of pathname of csidl folder 46) whose (exists folders of it) of folders of folder (pathname of parent folder of parent folder of csidl folder 46)
Now that you see the last “pathname”, let’s reduce it a tad further…
exists folder (following text of last “” of pathname of csidl folder 46) whose (exists folders of it) of folders of (parent folder of parent folder of csidl folder 46)
And the last parenthesis isn’t technically needed…
exists folder (following text of last “” of pathname of csidl folder 46) whose (exists folders of it) of folders of parent folder of parent folder of csidl folder 46
Maybe the other guys have a more elegant solution. It’s late and I’m going home 
Paul