Perhaps you should try some spelling variations:
"e factor" » "e factors", "one factor", "age factor", "de factor", "e factr", "5 factor"
"ex facto" » "sex factor", "ix factor", "de facto"
"de fact" » "de facto", "de fait", "e fact"
"e facto" » "de facto", "e fact", "5 facto"

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