Perhaps you should try some spelling variations:
forschungsberichte des » forschungsberichte der, forschungsbericht zum, forschungsbereiche und
forschungsbericht 3 » forschungsbericht zum, forschungsberichte der, forschungsbereichen 4
lane nordrhein » lande nordrhein, land nordrhein, landes nordrhein
3 landes » 3 landau, 3 lane, 3 lange

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: "((\"forschungsbericht ((3 landes) OR (3 land)) nordrhein-westfalen\") or (\"((forschungsbericht 3) OR (forschungsberichte des)) lane nordrhein-westfalen\"))".
• The words AND, OR and NOT may confuse the search; try adding quotes: "\"((\\"forschungsbericht ((3 landes) or (3 land)) nordrhein-westfalen\\") or (\\"((forschungsbericht 3) OR (forschungsberichte des)) lane nordrhein-westfalen\\"))\"".
• Removing quotes may allow a broader search: (( forschungsbericht ((3 landes) or (3 land)) nordrhein-westfalen ) or ( ((forschungsbericht 3) OR (forschungsberichte des)) lane nordrhein-westfalen )).