Perhaps you should try some spelling variations:
"world bank regional and doctoral studies" » "world bank regional and doctoral students", "world bank regional and doctoral student", "world bank regional and spectral studies", "world mask regional and doctoral studies", "world park regional and doctoral studies", "world urbano regional and doctoral studies"
"world lanka regional and sectoral studies" » "world lanka regional and sectional studies", "world lanka regional and spectral studies", "world lanka regional and sector studies", "world lanea regional and sectoral studies", "world batka regional and sectoral studies", "world panama regional and sectoral studies", "world banks regional and sectoral studies", "world lack regional and sectoral studies", "world lake regional and sectoral studies"
"world bank regional and cultural studies" » "world mask regional and cultural studies", "world park regional and cultural studies", "world urbano regional and cultural studies"

Try widening your search to All Fields.

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: (("world lanka regional and sectoral studies") OR ((("world bank regional and doctoral studies") OR ("world bank regional and cultural studies")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"world lanka regional and sectoral studies\") or (((\"world bank regional and doctoral studies\") OR (\"world bank regional and cultural studies\"))))".
• Removing quotes may allow a broader search: (( world lanka regional and sectoral studies ) or ((( world bank regional and doctoral studies ) OR ( world bank regional and cultural studies )))).
• Adding a wildcard symbol may retrieve word variants: (("world lanka regional and sectoral studies") or ((("world bank regional and doctoral studies") OR ("world bank regional and cultural studies"))))*.