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

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