Perhaps you should try some spelling variations:
"dose factor" » "noise factor", "one factor", "mode factor", "dose factors", "dosone factor", "dosage factor"
"de factor" » "de facto", "mode factor", "de factores", "de factors", "done factor", "dage factor"
"e factor" » "e factors", "one factor", "age factor"
"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 ("dose factor"))) OR ("de fait"))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"de factor\") OR (\"e factor\"))) or (\"dose factor\"))) or (\"de fait\"))*".
• Removing quotes may allow a broader search: (((((( de factor ) OR ( e factor ))) or ( dose factor ))) or ( de fait ))*.