Perhaps you should try some spelling variations:
passiv » passive, massiv
passiven » passiveen, massiven, passive, passion
passivere » passiveere, massivere, passiverer, passivieren, passivee, passivelye, passierte
passiver » passiveer, massiver, passive, passively, passiert
massiver » massive, massiven, massively
aktivierende » 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 passiven) OR ((passivere OR passiver) OR massiver)) OR aktivierende).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((passiv OR passiven) or ((passivere or passiver) or massiver)) or aktivierende)".
• Adding a wildcard symbol may retrieve word variants: (((passiv OR passiven) or ((passivere or passiver) or massiver)) or aktivierende)*.