Sometimes addressbook entries are not displayed but only the nepomuk search results. It's a timing issue as far as I could track it down: All results are only displayed if the query through akonadi finishes before the direct nepomuk query. Since it's usually the other way around addressbooks entries are not displayed. As far as I could track it down the matches are still added using addCompletionItem, but they are somehow not displayed. Reproducible: Always
*** Bug 296050 has been marked as a duplicate of this bug. ***
Patch which fixes the issue for me: https://git.reviewboard.kde.org/r/108961/
Fixed in 8c2bf14a2ba463435533c3696c13767d909da545. (4.10.2)