Perhaps you should try some spelling variations:
teachers social » teaching social
der transfer » der transfers, den transfer, peer transfer
transfer ai » transfers ai, transfer a, transfer asia
4.2.1 data » 4.3.1 data, 3.2.1 data, 4.2.2 data
ai marc » bei marc
luis 3 » luis f, luis c, luis a
3 der » _ der, 2 der

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: (( luis 3 der transfer ai marc ) OR ( luis ((2.1 data) OR (4.2.1 data)) teachers social _ ))~.
• Adding a wildcard symbol may retrieve word variants: (( luis 3 der transfer ai marc ) or ( luis ((2.1 data) or (4.2.1 data)) teachers social _ ))*.