Perhaps you should try some spelling variations:
passiv » passiven, passiver
passive » passivene, passivere
passivierung » passivenierung, passiverierung, aktivierung
passivener » passivenener, passiverener, passiven, passiver, passiverwerb
passiverer » passivenerer, passivererer, passiverwerb, passivieren, passiver
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 massiv) OR passive) OR (passivierung OR (passivener OR passiverer))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((passiv or massiv) or passive) or (passivierung or (passivener OR passiverer)))".
• Adding a wildcard symbol may retrieve word variants: (((passiv or massiv) or passive) or (passivierung or (passivener OR passiverer)))*.