Perhaps you should try some spelling variations:
passiven » passive, passion
passivieren » passivierende, passagieren, passivierender
passivierung » aktivierung
passieren » passiert
massigeren » massiger, massigen, massierer
massivere » massiver, massive, massively

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