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

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 massiverer)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((passiv OR passive) or (passiverer or massiverer))".
• Adding a wildcard symbol may retrieve word variants: ((passiv OR passive) or (passiverer or massiverer))*.