Perhaps you should try some spelling variations:
"a duncan sarah" » "a duncan adam", "a duncan gray", "ra duncan sarah", "_ duncan sarah", "j duncan sarah"
"jon duncan sir" » "john duncan sir", "j duncan sir", "colin duncan sir", "jon duncan i"
"ian duncan shaw" » "brian duncan shaw", "innes duncan shaw"

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: (("a duncan sarah") OR ((("jon duncan sir") OR ("ian duncan shaw")))).
• Removing quotes may allow a broader search: (( a duncan sarah ) or ((( jon duncan sir ) or ( ian duncan shaw )))).
• Adding a wildcard symbol may retrieve word variants: (("a duncan sarah") or ((("jon duncan sir") or ("ian duncan shaw"))))*.