Perhaps you should try some spelling variations:
"a robust e. heimann book" » "a robust e. german book", "_ robust e. heimann book", "a robust _. heimann book", "a robust end. heimann book", "a robust l1. heimann book"
"a robust a. heimann book" » "a robust a. german book", "_ robust a. heimann book", "a robust _. heimann book", "a robust cat. heimann book", "a robust lca. heimann book"
"a robot j. heilman book" » "a robot j. german book", "_ robot j. heilman book", "a robot _. heilman book", "a robot 1. heilman book", "a robot 5. heilman 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. heilman book") or ((("a robust e. heimann book") OR ("a robust a. heimann book"))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("a robot j. heilman book") OR ((("a robust e. heimann book") OR ("a robust a. heimann book")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"a robot j. heilman book\") or (((\"a robust e. heimann book\") OR (\"a robust a. heimann book\"))))".
• Removing quotes may allow a broader search: (( a robot j. heilman book ) or ((( a robust e. heimann book ) OR ( a robust a. heimann book )))).
• Adding a wildcard symbol may retrieve word variants: (("a robot j. heilman book") or ((("a robust e. heimann book") OR ("a robust a. heimann book"))))*.