Perhaps you should try some spelling variations:
"dde factor" » "dose factor", "mode factor", "one factor", "de factor", "ddose factor", "dmode factor", "dde factorr", "ddex factor", "dde factr", "dde faitor", "dde falcoor"
"de factor" » "e factor", "dose factor", "mode factor", "de factorr", "dex factor", "de factr", "de faitor", "de falcoor"
"e facto" » "e factor", "ex facto", "e fact"
"de facto" » "de factor", "dex facto", "de fact", "de faito", "e facto", "de falcoo"
"de fact" » "de fait", "e fact", "de falco"

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