Perhaps you should try some spelling variations:
passiv » massiv, passiven, passiver
passiverer » massiverer, passivenerer, passivererer, passivieren, passiver, passieren
passiverwerb » massiverwerb, passivenerwerb, passivererwerb
passive » massive, passivene, passivere
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 massiven) OR (passiverer OR passiverwerb)) OR (passive OR massive)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((passiv or massiven) or (passiverer OR passiverwerb)) or (passive or massive))".
• Adding a wildcard symbol may retrieve word variants: (((passiv or massiven) or (passiverer OR passiverwerb)) or (passive or massive))*.