Perhaps you should try some spelling variations:
"supply case importing countries." » "supply case exporting countries.", "supply case importing country.", "supply case reporting countries.", "supply gas importing countries.", "supply case supporting countries.", "supply cost importing countries.", "supply chain importing countries.", "supply curve importing countries."
"supply die interaction series." » "supply die interactions series.", "supply die interaction studies.", "supply die interaction terms.", "supply die interaktion series.", "supply time interaction series.", "supply like interaction series.", "supply driven interaction series."

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: (("supply die interaction series.") OR ("supply case importing countries."))~.
• Removing quotes may allow a broader search: (( supply die interaction series. ) or ( supply case importing countries. ))~.
• Adding a wildcard symbol may retrieve word variants: (("supply die interaction series.") or ("supply case importing countries."))*.