Perhaps you should try some spelling variations:
"jon duncan smith" » "jon duncan sir", "j duncan smith", "ian duncan smith", "colin duncan smith"
"jon duncan sarah" » "jon duncan adam", "jon duncan gray", "jon duncan shaw", "j duncan sarah", "ian duncan sarah", "colin duncan sarah"
"john duncan scott" » "john duncan scotus", "john duncan stone", "john dunton scott", "john dunning scott"

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: (((("jon duncan smith") OR ("jon duncan sarah"))) OR ("john duncan scott")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"jon duncan smith\") OR (\"jon duncan sarah\"))) or (\"john duncan scott\"))".
• Removing quotes may allow a broader search: (((( jon duncan smith ) OR ( jon duncan sarah ))) or ( john duncan scott )).
• Adding a wildcard symbol may retrieve word variants: (((("jon duncan smith") OR ("jon duncan sarah"))) or ("john duncan scott"))*.