Perhaps you should try some spelling variations:
"Supply grid integration theories." » "Supply grid integration theorems.", "Supply grid integrationstheorie 2.", "Supply grid integration theory."
"supply data integration theories." » "supply data integration theorems.", "supply data integrationstheorie 2.", "supply data integration theory.", "supply data integrity theories."
supply grid » supply crowd, supply great, support grid

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: (("Supply grid integration theories.") or ("supply data integration theories."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("Supply grid integration theories.") OR ("supply data integration theories.")).
• Removing quotes may allow a broader search: (( Supply grid integration theories. ) or ( supply data integration theories. )).
• Adding a wildcard symbol may retrieve word variants: (("Supply grid integration theories.") or ("supply data integration theories."))*.