Perhaps you should try some spelling variations:
passiv » passive, massiv, passiven
passivierender » passiveierender, massivierender, passivenierender, passivierende, aktivierender, passivieren
massively » massive
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 massively) OR (passivierender OR aktivierende)).
• Adding a wildcard symbol may retrieve word variants: ((passiv or massively) or (passivierender or aktivierende))*.