Perhaps you should try some spelling variations:
"model factors" » "models factors", "model factor", "model factory", "model factrs", "model factsrs"
"mode factor" » "model factor", "models factor", "model factory", "mode factr", "mode factsr"
"de facto" » "de fact", "de facts"

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