Perhaps you should try some spelling variations:
"de factor" » "de facto", "dose factor", "mode factor", "de factors", "done factor", "dage factor"
"e factor" » "e factors", "one factor", "age factor"
"e facts" » "5 facts", "8 facts", "e fact"
"de fait" » "de faits", "le fait", "se fait"

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: (((("de factor") OR ("e factor"))) OR ((("e facts") OR ("de fait")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"de factor\") OR (\"e factor\"))) or (((\"e facts\") or (\"de fait\"))))".
• Removing quotes may allow a broader search: (((( de factor ) OR ( e factor ))) or ((( e facts ) or ( de fait )))).
• Adding a wildcard symbol may retrieve word variants: (((("de factor") OR ("e factor"))) or ((("e facts") or ("de fait"))))*.