Perhaps you should try some spelling variations:
"import price integration theories." » "import price integration theorems.", "import price integrationstheorie 2.", "import price integration theory.", "import service integration theories.", "import trade integration theories.", "import price indexation theories.", "import prices integration theories.", "export price integration theories.", "export prices integration theories."
"efforts policies training services." » "efforts police training services.", "efforts policies targeting services.", "efforts policies changing services.", "efforts policies planning services.", "efforts policies banking services.", "effects policies training services.", "export policies training services.", "forms policies training services."

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: (("import price integration theories.") or ("efforts policies training services."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("import price integration theories.") OR ("efforts policies training services.")).
• Removing quotes may allow a broader search: (( import price integration theories. ) or ( efforts policies training services. )).
• Adding a wildcard symbol may retrieve word variants: (("import price integration theories.") or ("efforts policies training services."))*.