Perhaps you should try some spelling variations:
passiver » passiven, passiert
passivere » passivene, passierte, passiverer, massivere, passivieren
passively » massively, passivity, passiven
passivelyen » massivelyen, passivityen, passivenen
passierte » passiert, klassierte, passieren

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