Perhaps you should try some spelling variations:
passiv » passiven, passiver
passive » passivene, passivere
aktivierende » aktivierenden, aktivieren, praktizierende
motivierende » motivieren, motivierte, motivierten
massiv » massive

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 (aktivierende OR motivierende)) OR massiv) OR passive).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((passiv or (aktivierende OR motivierende)) or massiv) or passive)".
• Adding a wildcard symbol may retrieve word variants: (((passiv or (aktivierende OR motivierende)) or massiv) or passive)*.