Perhaps you should try some spelling variations:
"a robot j. heimann books" » "a robot j. demand books", "a robot j. german books", "_ robot j. heimann books", "a robot _. heimann books", "a robot 1. heimann books", "a robot 5. heimann books"
"a robert _. hermann book" » "a robert _. hermann broch", "a robert _. hermann lohr", "a robert _. hermann von", "3 robert _. hermann book", "dr robert _. hermann book"
"a robust end. german book" » "a robust end. german books", "a robust end. german food", "a robust read. german book", "a robust bound. german book", "_ robust end. german book"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("a robot j. heimann books") or ("a robert _. hermann book"))) or ("a robust end. german book"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("a robot j. heimann books") OR ("a robert _. hermann book"))) OR ("a robust end. german book")).
• Removing quotes may allow a broader search: (((( a robot j. heimann books ) or ( a robert _. hermann book ))) or ( a robust end. german book )).
• Adding a wildcard symbol may retrieve word variants: (((("a robot j. heimann books") or ("a robert _. hermann book"))) or ("a robust end. german book"))*.