Perhaps you should try some spelling variations:
passiv » passive, massiv, passiven
passivierung » passiveierung, massivierung, passivenierung, aktivierung
passivieren » passiveieren, massivieren, passivenieren, passivierende, passagieren, passivierender
passieren » passiert, passiven

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: ((passiv OR passion) OR ((passivierung OR passivieren) OR passieren)).
• Adding a wildcard symbol may retrieve word variants: ((passiv or passion) or ((passivierung or passivieren) or passieren))*.