Perhaps you should try some spelling variations:
"model factors" » "models factors", "model factor", "model factory"
"de factor" » "e factor", "dose factor", "mode factor", "de factorr", "dex factor", "de factr", "de falcoor", "de faconor"
"de facto" » "de factor", "dex facto", "de fact", "e facto", "de falcoo", "de facono"
"e facto" » "e factor", "ex facto", "e fact"
"de fact" » "e fact", "de falco", "de facon"
"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 ("model factors"))) OR ((("de facto") OR ("e facto"))))) OR ((("de fact") OR ("de fait")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"de factor\") or (\"model factors\"))) or (((\"de facto\") OR (\"e facto\"))))) or (((\"de fact\") or (\"de fait\"))))".
• Removing quotes may allow a broader search: (((((( de factor ) or ( model factors ))) or ((( de facto ) OR ( e facto ))))) or ((( de fact ) or ( de fait )))).
• Adding a wildcard symbol may retrieve word variants: (((((("de factor") or ("model factors"))) or ((("de facto") OR ("e facto"))))) or ((("de fact") or ("de fait"))))*.