Perhaps you should try some spelling variations:
passiver » passive, passiven, passively
passiveren » passiveen, passivenen, passivelyen, passivieren, passieren, passiven
passiverern » passiveern, passivenern, passivelyern, passiverwerb, passieren, passivieren, passiverwerbn, passivierenn, passierenn
passiverer » passiveer, passivener, passivelyer, passiverwerb, passivieren, passieren

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: ((passiver OR (passion OR (passiveren OR passiverern))) OR passiverer).
• Adding a wildcard symbol may retrieve word variants: ((passiver or (passion or (passiveren or passiverern))) or passiverer)*.