Perhaps you should try some spelling variations:
"biographer" » "biographies", "biographien", "biography"
"biographie" » "biographies", "biography", "biographical"
"biographierten" » "biographiesrten", "biographyrten", "biographicalrten", "biographiedaten", "biographiert", "bibliographierten"

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: (("biographer" OR "biographie") OR "biographierten").
• Removing quotes may allow a broader search: (( biographer or biographie ) or biographierten ).
• Adding a wildcard symbol may retrieve word variants: (("biographer" or "biographie") or "biographierten")*.