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 robot j. heilman book", "a robert e. heilman book"
"a robert _. heilman book" » "a robert _. german book", "3 robert _. heilman book", "dr robert _. heilman book", "a robot _. heilman book"
"a robust a. hellman joel" » "_ robust a. hellman joel", "a robust _. hellman joel", "a robust cat. hellman joel", "a robust lca. hellman joel"

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• Performing a fuzzy search may retrieve terms with similar spellings: (((("a robert j. heilman book") or ("a robert _. heilman book"))) or ("a robust a. hellman joel"))~.
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