Perhaps you should try some spelling variations:
passiv » passiven, passiver
passive » passivene, passivere
passivener » passivenener, passiverener, passiverer, passiven, passiver
passiveren » passiveneren, passivereren, passivieren, passieren, passiverer
massiv » massive

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