Perhaps you should try some spelling variations:
german » germans (Expand Search)
gehrmann » hermann (Expand Search), germans (Expand Search), herrmann (Expand Search)
national » nationala (Expand Search), nationaler (Expand Search), nationales (Expand Search)
nationalen » nationalaen (Expand Search), nationaleren (Expand Search), nationalesen (Expand Search)
nationale » nationalae (Expand Search), nationalere (Expand Search), nationalese (Expand Search)
academie » akademie (Expand Search), academia (Expand Search), academic (Expand Search)

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: "(german OR gehrmann) (national OR (nationalen OR nationale)) academie of sciences leopoldina~".
• Adding a wildcard symbol may retrieve word variants: (german OR gehrmann) (national OR (nationalen OR nationale)) academie of sciences leopoldina*.