Perhaps you should try some spelling variations:
passiv » massiv, passiver
passiven » massiven, passiveren, passion
passivenener » massivenener, passiverenener, passionener, passivierender, passiverer
passivererwerb » massivererwerb, passiverererwerb, passiverwerb
passive » massive, passivere

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 passiven) OR (passivenener OR passivererwerb)) OR passive).
• Adding a wildcard symbol may retrieve word variants: (((passiv or passiven) or (passivenener or passivererwerb)) or passive)*.