Perhaps you should try some spelling variations:
a robert » 3 robert, dr robert, a robust
robert j » robert _, robert e
robert a » robert _, robert e
heilmann » heilemann, heitmann, heilman
book » books, ebook
ebookss » ebooksss, eebookss, ebooks
eebookss » eebooksss, eeebookss, eebooks, ebooks
eeebookss » eeebooksss, eeeebookss, eeebooks, eebooks

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 j. heilmann book ) OR ( a robert a. heimann ((ebookss OR eebookss) OR eeebookss) ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( a robert j. heilmann book ) or ( a robert a. heimann ((ebookss OR eebookss) or eeebookss) ))~".
• Adding a wildcard symbol may retrieve word variants: (( a robert j. heilmann book ) or ( a robert a. heimann ((ebookss OR eebookss) or eeebookss) ))*.