Perhaps you should try some spelling variations:
passiv » massiv, passiven
passive » massive, passivene
passiverer » massiverer, passivenerer, passiverwerb, passivieren, passieren, passivener, passivelyer, passierter
passiver » massiver, passivener, passiven, passively, passiert
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 (massiverer OR (passiverer OR passiver))))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(passiv or (passive or (massiverer or (passiverer OR passiver))))*".