Perhaps you should try some spelling variations:
"johann gottlieb richter" » "johann gottlieb fichte", "johann gottlieb roger", "johann gottfried richter"
"johann gottlieb dichte" » "johann gottfried dichte", "johann gottlieb fichte", "johann gottlieb fichtes", "johann gottlieb michah"

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"johann gottlieb dichte\") OR (\"johann gottlieb richter\"))".
• Removing quotes may allow a broader search: (( johann gottlieb dichte ) OR ( johann gottlieb richter )).
• Adding a wildcard symbol may retrieve word variants: (("johann gottlieb dichte") OR ("johann gottlieb richter"))*.