Perhaps you should try some spelling variations:
"historia of philosophy" » "historic of philosophy", "histories of philosophy"
"historians of philosophy" » "historicns of philosophy", "historiesns of philosophy", "histories of philosophy"

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: (((("historia of philosophy") OR ("historical of philosophy"))) OR ("historians of philosophy")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"historia of philosophy\") OR (\"historical of philosophy\"))) or (\"historians of philosophy\"))".
• Removing quotes may allow a broader search: (((( historia of philosophy ) OR ( historical of philosophy ))) or ( historians of philosophy )).
• Adding a wildcard symbol may retrieve word variants: (((("historia of philosophy") OR ("historical of philosophy"))) or ("historians of philosophy"))*.