Perhaps you should try some spelling variations:
"dose factor" » "noise factor", "mode factor", "moore factor", "dose factors", "dosage factor"
"e factor" » "e factors", "age factor"
"one factor" » "one factors", "onage factor"
"de fact" » "de facto", "de fait", "e fact"

You may be able to get more results by adjusting your search query.

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