The common dialog box reference is part of the Windows platform SDK which you can download from the MSDN website. You probably can find the same reference online here ( I say probably because these things seem to change as soon as you bookmark them )

However having look at the local copy of said documentation that comes with visual studio - I can tell you that the document search is not part of that library - the find dialog is limited to the 'Find' that you get on the 'Edit' menu of windows applications.

/J\