Perhaps you should try some spelling variations:
"a robert e. hermann book" » "a robert e. hermann broch", "a robert e. hermann lohr", "a robert e. hermann von", "3 robert e. hermann book", "dr robert e. hermann book", "a robust e. hermann book", "a robert _. hermann book", "a robert j. hermann book"
"a robert e. german book" » "a robert e. german books", "a robert e. german food", "3 robert e. german book", "dr robert e. german book", "a robust e. german book", "a robert _. german book", "a robert j. german book"
"a robert b. heimann book" » "3 robert b. heimann book", "dr robert b. heimann book", "a robust b. heimann book", "a robert _. heimann book", "a robert j. heimann book", "a robert a. heimann 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 robert e. hermann book") OR ("a robert e. german book"))) or ("a robert b. heimann book"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("a robert e. hermann book") OR ("a robert e. german book"))) OR ("a robert b. heimann book")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"a robert e. hermann book\") OR (\"a robert e. german book\"))) or (\"a robert b. heimann book\"))".
• Removing quotes may allow a broader search: (((( a robert e. hermann book ) OR ( a robert e. german book ))) or ( a robert b. heimann book )).
• Adding a wildcard symbol may retrieve word variants: (((("a robert e. hermann book") OR ("a robert e. german book"))) or ("a robert b. heimann book"))*.