Perhaps you should try some spelling variations:
"a robert j. heilman book" » "a robert j. german book", "3 robert j. heilman book", "dr robert j. heilman book", "a robust j. heilman book"
"a robert e. heilman book" » "a robert e. german book", "3 robert e. heilman book", "dr robert e. heilman book", "a robust e. heilman book"
"a robert _. heilmann book" » "3 robert _. heilmann book", "dr robert _. heilmann book", "a robust _. heilmann 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 _. heilmann book") or ("a robert j. heilman book"))) or ("a robert e. heilman book"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("a robert _. heilmann book") OR ("a robert j. heilman book"))) OR ("a robert e. heilman book")).
• Removing quotes may allow a broader search: (((( a robert _. heilmann book ) or ( a robert j. heilman book ))) or ( a robert e. heilman book )).
• Adding a wildcard symbol may retrieve word variants: (((("a robert _. heilmann book") or ("a robert j. heilman book"))) or ("a robert e. heilman book"))*.