Perhaps you should try some spelling variations:
gail robert » gal robert, davis robert, blair robert
robert e » robert _, robert j
a robert » gal robert
a robust » _ robust
heitmann » heinemann, hermann, hartmann
book » books, ebook
eebooks » eebookss, eeebooks, ebooks
heimann » hermann, heinemann

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( gail robert e. heitmann book ) or ( ((a robert) OR (a robust)) _. heimann eebooks ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( gail robert e. heitmann book ) OR ( ((a robert) OR (a robust)) _. heimann eebooks )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( gail robert e. heitmann book ) or ( ((a robert) OR (a robust)) _. heimann eebooks ))".
• Adding a wildcard symbol may retrieve word variants: (( gail robert e. heitmann book ) or ( ((a robert) OR (a robust)) _. heimann eebooks ))*.