Perhaps you should try some spelling variations:
"john dunning smith" » "john turning smith", "john dennis smith", "john using smith", "john jennings smith", "john dunton smith"
"brian duncan sir" » "ian duncan sir", "bruce duncan sir", "brian duncan i", "brian duncan sarah"
"jon duncan smith" » "jon duncan sarah", "jon duncan scott", "john duncan smith", "j duncan smith", "ian duncan smith"

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: (("brian duncan sir") OR ((("jon duncan smith") OR ("john dunning smith")))).
• Removing quotes may allow a broader search: (( brian duncan sir ) or ((( jon duncan smith ) or ( john dunning smith )))).
• Adding a wildcard symbol may retrieve word variants: (("brian duncan sir") or ((("jon duncan smith") or ("john dunning smith"))))*.