Perhaps you should try some spelling variations:
"export prices integration theories." » "export prices integration theorems.", "export prices integrationstheorie 2.", "export prices integration theory.", "export price integration theories.", "export process integration theories.", "export policies integration theories.", "import prices integration theories."
"efforts policies meeting services." » "effects policies meeting services.", "export policies meeting services.", "forms policies meeting services.", "efforts policies being services.", "efforts policies dealing services.", "efforts policies sealing services.", "efforts policies testing services.", "efforts policies heating services.", "efforts policies marketing services."

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: (("export prices integration theories.") OR ("efforts policies meeting services."))~.
• Removing quotes may allow a broader search: (( export prices integration theories. ) or ( efforts policies meeting services. ))~.
• Adding a wildcard symbol may retrieve word variants: (("export prices integration theories.") or ("efforts policies meeting services."))*.