Perhaps you should try some spelling variations:
"supply side integration theories." » "supply side integration theorems.", "supply side integrationstheorie 2.", "supply side integration theory.", "supply die integration theories.", "supply de integration theories.", "supply life integration theories."
"support syria irrigation schemes." » "support syria irrigation scheme.", "support syria irrigation systems.", "support africa irrigation schemes.", "support drip irrigation schemes.", "support surge irrigation schemes.", "support social irrigation schemes.", "support agri irrigation schemes."

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: (("supply side integration theories.") or ("support syria irrigation schemes."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply side integration theories.") OR ("support syria irrigation schemes.")).
• Removing quotes may allow a broader search: (( supply side integration theories. ) or ( support syria irrigation schemes. )).
• Adding a wildcard symbol may retrieve word variants: (("supply side integration theories.") or ("support syria irrigation schemes."))*.