Perhaps you should try some spelling variations:
passiven » passion
massively » massive
passiveeren » passieren, passiverer
passivieren » passieren, passagieren, passivierender
passivierende » passierende, passagierende, passivierenderde, passivierender, aktivierende, passerende
passivierung » aktivierung

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