Perhaps you should try some spelling variations:
states methodology » surveys methodology, sciences methodology
economic studies » economic status
aims methodology » aims methodological, 3 methodology, 2 methodology
studies united » sources united, states united, subsidies united
studies und » studien und, studie und, studies using
united aims » united army
und states » und status, bound states, und staaten

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( economic studies und states methodology ) or ( economic studies united aims methodology ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( economic studies und states methodology ) OR ( economic studies united aims methodology )).
• Adding a wildcard symbol may retrieve word variants: (( economic studies und states methodology ) or ( economic studies united aims methodology ))*.