Perhaps you should try some spelling variations:
communications communication » communication communication, communicating communication, communication communicating
communication basic » communications basic, communication based, communication asia
basic dimensions » based dimension, pacific dimensions, design dimensions
index theorem » index theory
index free » index tree, index from

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

• Performing a fuzzy search may retrieve terms with similar spellings: communications communication basic dimensions ((index free) or (index theorem))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: communications communication basic dimensions ((index free) OR (index theorem)).
• Adding a wildcard symbol may retrieve word variants: communications communication basic dimensions ((index free) or (index theorem))*.