Perhaps you should try some spelling variations:
"a robot e. hellman book" » "a robot e. german book", "_ robot e. hellman book", "a robust e. hellman book", "a robot _. hellman book", "a robot 1. hellman book", "a robot 5. hellman book"
"_ robust e. heilman book" » "_ robust e. german book", "_ robert e. heilman book", "_ robust _. heilman book", "_ robust a. heilman book", "_ robust end. heilman book"
"dr robert e. hellman joel" » "dr robert _. hellman joel", "dr robert j. hellman joel"

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