Perhaps you should try some spelling variations:
passiver » passive, passively, passiert
passiven » passive, passion
passivieren » passivierung, passieren, passagieren
passivierende » passivierungde, passierende, passagierende, passivierender, aktivierende, passivierung

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 (passiven OR (passiveand OR (passivieren OR passivierende)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(passiver or (passiven or (passiveand or (passivieren OR passivierende))))".
• Adding a wildcard symbol may retrieve word variants: (passiver or (passiven or (passiveand or (passivieren OR passivierende))))*.