Perhaps you should try some spelling variations:
"historian" » "historians", "historical", "historicaln", "historiansn"
"historien" » "historie", "historikern", "historians"
"historikerin" » "historikern", "historiker"
"historikers" » "historiker", "historikern"
"historia" » "historical", "historians"
"historic" » "historical"

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: (("historian" OR (("histories" OR "historien") OR ("historikerin" OR "historikers"))) OR ("historia" OR "historic")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"historian\" or ((\"histories\" or \"historien\") or (\"historikerin\" OR \"historikers\"))) or (\"historia\" or \"historic\"))".
• Removing quotes may allow a broader search: (( historian or (( histories or historien ) or ( historikerin OR historikers ))) or ( historia or historic )).
• Adding a wildcard symbol may retrieve word variants: (("historian" or (("histories" or "historien") or ("historikerin" OR "historikers"))) or ("historia" or "historic"))*.