Perhaps you should try some spelling variations:
"import re integration theory." » "import re integration through.", "import re information theory.", "import re innovation theory.", "import de integration theory.", "import fare integration theory.", "import care integration theory.", "import _ integration theory.", "import price integration theory.", "import share integration theory."
"export policies testing services." » "export policies meeting services.", "export policies using services.", "export policies being services.", "export policies existing services.", "export policies lending services.", "export policies training services.", "import policies testing services.", "support policies testing services.", "efforts policies testing 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 re integration theory.") or ("export policies testing services."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("import re integration theory.") OR ("export policies testing services.")).
• Removing quotes may allow a broader search: (( import re integration theory. ) or ( export policies testing services. )).
• Adding a wildcard symbol may retrieve word variants: (("import re integration theory.") or ("export policies testing services."))*.