Perhaps you should try some spelling variations:
passiv » massiv, passiven
passive » massive, passivene
passiverer » massiverer, passivenerer, passiverwerb, passivieren, passieren, passivener, passivelyer, passierter
passivener » massivener, passivenener, passiven, passiverwerb
passiver » massiver, passivener, passiven, passively, passiert

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