Perhaps you should try some spelling variations:
communications applications » communication applications, telecommunications applications, telecommunication applications
applications set » applications seta, applications self, applications soft
spaces » dspaces
dspaces » ddspaces
ddspaces » dddspaces
space » dspace

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: communications applications set (((spaces OR dspaces) OR dspaces) OR ddspaces) euclidean space~.
• Adding a wildcard symbol may retrieve word variants: communications applications set (((spaces or dspaces) or dspaces) or ddspaces) euclidean space*.