Perhaps you should try some spelling variations:
"a robert e. heilman book" » "gal robert e. heilman book", "a robust e. heilman book", "a robert _. heilman book", "a robert e. heilmann book", "a robert e. hellman book", "a robert e. heitmann book", "a robert e. heilman books", "a robert e. heilman ebook"
"a robert j. heilman book" » "gal robert j. heilman book", "a robust j. heilman book", "a robert _. heilman book", "a robert j. heilmann book", "a robert j. hellman book", "a robert j. heitmann book", "a robert j. heilman books", "a robert j. heilman ebook"
"_ robust e. heilman book" » "_ robust _. heilman book", "_ robust e. heilmann book", "_ robust e. hellman book", "_ robust e. heitmann book", "_ robust e. heilman books", "_ robust e. heilman ebook"

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: (((("a robert e. heilman book") OR ("a robert j. heilman book"))) OR ("_ robust e. heilman book"))~.
• Removing quotes may allow a broader search: (((( a robert e. heilman book ) or ( a robert j. heilman book ))) or ( _ robust e. heilman book ))~.
• Adding a wildcard symbol may retrieve word variants: (((("a robert e. heilman book") or ("a robert j. heilman book"))) or ("_ robust e. heilman book"))*.