Perhaps you should try some spelling variations:
passiv » massiv, passiver
passiven » massiven, passiveren, passion
passiveren » massiveren, passivereren, passivieren, passieren, passiver
passiverer » massiverer, passivererer, passiverwerb, passivieren, passiver
passive » massive, passivere

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