Perhaps you should try some spelling variations:
"scope research theories" » "scope research theory", "scope research themes", "scope research topics", "core research theories", "code research theories", "europe research theories"
"scope research studies" » "core research studies", "code research studies", "europe research studies"
"scope research study" » "core research study", "code research study", "europe research study"
"cure research studies" » "curve research studies", "care research studies", "core research 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: (((((("scope research studies") OR ("cure research studies"))) OR ("scope research study"))) OR ("scope research theories")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"scope research studies\") OR (\"cure research studies\"))) or (\"scope research study\"))) or (\"scope research theories\"))".
• Removing quotes may allow a broader search: (((((( scope research studies ) OR ( cure research studies ))) or ( scope research study ))) or ( scope research theories )).
• Adding a wildcard symbol may retrieve word variants: (((((("scope research studies") OR ("cure research studies"))) or ("scope research study"))) or ("scope research theories"))*.