Perhaps you should try some spelling variations:
economic sanctions » economic conditions, economic sectors, economic relations
economic sections » economic section, economic reactions, economic sectors
economic history » economic theory, economic sectors

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: ((economic history) OR (((economic sections) OR (economic sanctions)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((economic history) or (((economic sections) OR (economic sanctions))))".
• Adding a wildcard symbol may retrieve word variants: ((economic history) or (((economic sections) OR (economic sanctions))))*.