Perhaps you should try some spelling variations:
passiv » massiv, passiven, passiver
passive » massive, passivene, passivere
passivierung » massivierung, passivenierung, passiverierung, aktivierung
massiven » passiven, massively, massiv

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