Perhaps you should try some spelling variations:
duncan sarah » duncan adam, duncan gray, duncan shaw
ian duncan » brian duncan, innes duncan
jon duncan » john duncan, j duncan, colin duncan
a duncan » ra duncan, _ duncan, j 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: (( ((ian duncan) OR (jon duncan)) sarah ) OR ( a duncan sarah )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((ian duncan) OR (jon duncan)) sarah ) or ( a duncan sarah ))".
• Adding a wildcard symbol may retrieve word variants: (( ((ian duncan) OR (jon duncan)) sarah ) or ( a duncan sarah ))*.