Perhaps you should try some spelling variations:
passiv » massiv, passiven, passiver
passiverer » massiverer, passivenerer, passivererer, passiverwerb, passivieren, passiver
passive » massive, passivene, passivere
massiver » passiver, massively, massiv
massiven » passiven, massively, massiv

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 massiver) OR massiven) OR passiverer) OR (passive OR massive)).
• Adding a wildcard symbol may retrieve word variants: ((((passiv or massiver) or massiven) or passiverer) or (passive or massive))*.