Perhaps you should try some spelling variations:
passiv » massiv
passive » massive
passiven » massiven, passion
passiverer » massiverer, passiverwerb, passivieren, passieren, passivelyer, passierter
passiver » massiver, passively, passiert
massiver » massive, massiven, massively

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