Perhaps you should try some spelling variations:
economic rents » economic trends, economic risks, economic reforms
recherche und » recherche en, recherche d'une, recherche prend
economic rent » economic report, economic trends, economic agents
studi per » studie der
studia ve » studie v, studia 4, studia a
studi e » studie 2, studi di, studie _

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((((studi e) or (studia ve))) or (studi per)) recherche und ((economic rents) or (economic rent)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((studi e) OR (studia ve))) OR (studi per)) recherche und ((economic rents) OR (economic rent)) ;.
• Adding a wildcard symbol may retrieve word variants: ((((studi e) or (studia ve))) or (studi per)) recherche und ((economic rents) or (economic rent)) ;*.