Perhaps you should try some spelling variations:
german ebookss » german books, german book
gail robert » hall robert, ball robert, marill robert
dahl robert » hall robert, ball robert, deal robert
gal robert » hall robert
heilmann » heilemann, heimann, heitmann
book » books, ebook
ebookss » ebooksss, eebookss

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) OR (dahl robert)) e. heilmann book ) or ( gal robert _. german ebookss ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ((gail robert) OR (dahl robert)) e. heilmann book ) OR ( gal robert _. german ebookss )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((gail robert) OR (dahl robert)) e. heilmann book ) or ( gal robert _. german ebookss ))".
• Adding a wildcard symbol may retrieve word variants: (( ((gail robert) OR (dahl robert)) e. heilmann book ) or ( gal robert _. german ebookss ))*.