Perhaps you should try some spelling variations:
zur islamforschung » zur dialogforschung, zur raumforschung, zur feldforschung
essener beitrage » essen beitrage, eigenes beitrage, segner beitrage
dialektforschung » marktforschung, begleitforschung, impaktforschung

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: essener beitrage ((zur islamforschung) OR (zur (dialogforschung OR dialektforschung))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "essener beitrage ((zur islamforschung) or (zur (dialogforschung OR dialektforschung)))".
• Adding a wildcard symbol may retrieve word variants: essener beitrage ((zur islamforschung) or (zur (dialogforschung OR dialektforschung)))*.