Perhaps you should try some spelling variations:
"western europe sources." » "eastern europe sources.", "western european sources."
"western crop studies." » "western crops studies.", "western cross studies.", "western crete studies.", "western group studies.", "western erp studies.", "western hop studies."
"western eyes studies." » "western diet studies.", "western genes studies.", "western ages studies.", "western ones studies."

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("western europe sources.") or ((("western crop studies.") or ("western eyes studies."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("western europe sources.") OR ((("western crop studies.") OR ("western eyes studies.")))).
• Removing quotes may allow a broader search: (( western europe sources. ) or ((( western crop studies. ) or ( western eyes studies. )))).
• Adding a wildcard symbol may retrieve word variants: (("western europe sources.") or ((("western crop studies.") or ("western eyes studies."))))*.