Perhaps you should try some spelling variations:
"support policies integration theories." » "support policy integration theories.", "support policies international theories.", "support political integration theories.", "support policies integration theorems.", "support policies integrationstheorie 2.", "support policies integration theory."
"support water irrigation schemes." » "support water irrigation scheme.", "support water irrigation systems.", "support scale irrigation schemes.", "support canal irrigation schemes.", "support farm irrigation schemes.", "support chapter irrigation schemes.", "support greater irrigation schemes.", "support better irrigation schemes."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("support water irrigation schemes.") or ("support policies integration theories."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("support water irrigation schemes.") OR ("support policies integration theories.")).
• Removing quotes may allow a broader search: (( support water irrigation schemes. ) or ( support policies integration theories. )).
• Adding a wildcard symbol may retrieve word variants: (("support water irrigation schemes.") or ("support policies integration theories."))*.