Perhaps you should try some spelling variations:
"export ratios integration theories." » "export ratios integration theorems.", "export ratios integrationstheorie 2.", "export ratios integration theory.", "export options integration theories.", "export migration integration theories.", "export national integration theories.", "export ratio integration theories.", "export duties integration theories."
"import data banking series." » "import data banking services.", "import data making series.", "import data banking service.", "import data taking series.", "import data linking series.", "import data asking series.", "import duty banking series."

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

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