Perhaps you should try some spelling variations:
passiv » passive, passiven, passiver
passivene » passiveene, passivenene, passiverene, passiven, passiveand, passive
passiverer » passiveerer, passivenerer, passivererer, passiverwerb, passivieren, passiver
aktivierenden » aktivieren, motivierende
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 passivene) OR aktivierenden) OR massiv) OR passiverer).
• Adding a wildcard symbol may retrieve word variants: ((((passiv or passivene) or aktivierenden) or massiv) or passiverer)*.