Perhaps you should try some spelling variations:
"support 3 integration theories." » "support 3 integration theorems.", "support 3 integrationstheorie 2.", "support 3 integration theory.", "support die integration theories.", "support der integration theories.", "support data integration theories.", "support _ integration theories.", "support a integration theories.", "support 4 integration theories."
"import dat_ integration schemes." » "import dat_ integration schengen.", "import dat_ irrigation schemes.", "import dat_ integration regimes.", "import data integration schemes.", "import dutch integration schemes.", "import _ integration schemes.", "import duty integration schemes.", "import dutie integration schemes."

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: (("import dat_ integration schemes.") OR ("support 3 integration theories."))~.
• Removing quotes may allow a broader search: (( import dat_ integration schemes. ) or ( support 3 integration theories. ))~.
• Adding a wildcard symbol may retrieve word variants: (("import dat_ integration schemes.") or ("support 3 integration theories."))*.