Perhaps you should try some spelling variations:
passiv » passive, massiv, passiven
passivieren » passiveieren, massivieren, passivenieren, passivierende, passivierung, passieren
passiveieren » passiveeieren, massiveieren, passiveneieren, passionierten, passivierende, passieren
massiver » massive, massiven, passiver
aktivierenden » aktivieren, motivierende

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 ((passivieren OR passiveieren) OR massiver)) OR aktivierenden).
• Adding a wildcard symbol may retrieve word variants: ((passiv or ((passivieren or passiveieren) or massiver)) or aktivierenden)*.