Perhaps you should try some spelling variations:
passiv » massiv, passiven, passiver
passiverierung » massiverierung, passivenerierung, passivererierung, passivierung, passivierungs
passiverwerb » massiverwerb, passivenerwerb, passivererwerb, passiverer
passive » massive, passivene, 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 (passiverierung OR passiverwerb)) OR passive).
• Adding a wildcard symbol may retrieve word variants: ((passiv or (passiverierung or passiverwerb)) or passive)*.