Perhaps you should try some spelling variations:
"supply chain integrationstheorie 2." » "supply eine integrationstheorie 2.", "supply der integrationstheorie 2.", "supply chain integrationstheorie fur.", "supply chain integration theories.", "supply chain interpretationstheorie 2."
"supply grid irrigation scheme." » "supply grid irrigation systems.", "supply grain irrigation scheme.", "supply drip irrigation scheme.", "supply gray irrigation scheme.", "supply crowd irrigation scheme.", "supply great irrigation scheme.", "support grid irrigation scheme."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("supply chain integrationstheorie 2.") or ("supply grid irrigation scheme."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply chain integrationstheorie 2.") OR ("supply grid irrigation scheme.")).
• Removing quotes may allow a broader search: (( supply chain integrationstheorie 2. ) or ( supply grid irrigation scheme. )).
• Adding a wildcard symbol may retrieve word variants: (("supply chain integrationstheorie 2.") or ("supply grid irrigation scheme."))*.