Perhaps you should try some spelling variations:
source based » resource based, resources based
edwards c » edwards _, edwards a, edwards d
c source » 2 source, 3 source, 5 source
d choice » 3 choice, 1 choice, 4 choice
5 choice » _ choice, 2 choice, 3 choice

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: (( edwards c source based ) OR ( edwards ((d choice) OR (5 choice)) based )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( edwards c source based ) or ( edwards ((d choice) OR (5 choice)) based ))".
• Adding a wildcard symbol may retrieve word variants: (( edwards c source based ) or ( edwards ((d choice) OR (5 choice)) based ))*.