Perhaps you should try some spelling variations:
integration theory » integration through, information theory, innovation theory
internet services » internet service
der integration » zur integration, sector integration
via internet » im internet, iii internet, mit internet
support der » support de, support under, support deep
report via » report eiu, report a, report di

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: (( support der integration theory. ) OR ( report via internet services. ))~.
• Adding a wildcard symbol may retrieve word variants: (( support der integration theory. ) or ( report via internet services. ))*.