Perhaps you should try some spelling variations:
"support data integration theories." » "support data integration theorems.", "support data integrationstheorie 2.", "support data integration theory.", "support data integrity theories.", "support a integration theories.", "support de integration theories."
"import data irrigation schemes." » "import data irrigation scheme.", "import data irrigation systems.", "import delta irrigation schemes.", "import canal irrigation schemes.", "import water irrigation schemes.", "import duty 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: (("import data irrigation schemes.") or ("support data integration theories."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("import data irrigation schemes.") OR ("support data integration theories."))*.
• Removing quotes may allow a broader search: (( import data irrigation schemes. ) or ( support data integration theories. ))*.