Perhaps you should try some spelling variations:
"international worker economy series" » "international workers economy series", "international work economy series", "international working economy series", "international worker economic series", "international workers economic series", "international market economy series"
"international plant economics series" » "international peace economics series", "international panel economics series", "international migrant economics series", "international land economics series", "international plants economic series", "international grants economics series"

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (("international worker economy series") or ("international plant economics series"))~.
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