Google Drive documents results used to be shown below Gmail search results. That option was a labs enabled tool where when you searched Gmail you would see matching Google Drive documents below the email results. Is there a way to re-enable that? It appears Google has disabled that function.
This is a "Google Apps for Business" account.
"Apps Search" does not appear under Labs in Settings for any users even though it is enabled in Domain Admin > Apps > Google Apps > Settings for Gmail > Labs