Perhaps you should try some spelling variations:
fogel robert » jovel roberto, fimbel robert, wrobel robert
robert e » robert _, robert j
a robust » _ robust
heilmann » heilemann, heimann, heitmann
book » books, ebook
redebooks » redebookss, redeebooks
codebooks » codebookss, codeebooks

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: (( fogel robert e. heilmann book ) OR ( a robust _. hartmann (redebooks OR codebooks) ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( fogel robert e. heilmann book ) or ( a robust _. hartmann (redebooks OR codebooks) ))~".
• Adding a wildcard symbol may retrieve word variants: (( fogel robert e. heilmann book ) or ( a robust _. hartmann (redebooks OR codebooks) ))*.