Perhaps you should try some spelling variations:
brian duncan » bruce duncan
ian duncan » jon duncan, innes duncan
a duncan » ra duncan, _ duncan, mr duncan
m duncan » mr duncan, _ duncan
j duncan » _ duncan, mr duncan

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) OR (ian duncan)) sarah ) OR ( ((((a duncan) OR (m duncan))) OR (j duncan)) sarah )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((brian duncan) or (ian duncan)) sarah ) or ( ((((a duncan) OR (m duncan))) or (j duncan)) sarah ))".
• Adding a wildcard symbol may retrieve word variants: (( ((brian duncan) or (ian duncan)) sarah ) or ( ((((a duncan) OR (m duncan))) or (j duncan)) sarah ))*.