Perhaps you should try some spelling variations:
passiv » passive, massiv, passiven
passiverer » passiveerer, massiverer, passivenerer, passiverwerb, passivieren, passiver
massivere » massiver, massive, massively
aktivierende » aktivierenden, aktivieren, praktizierende
motivierende » motivieren, motivierte, motivierten

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