Perhaps you should try some spelling variations:
political communication » optical communications
optic communication » optical communications, grid communication, mobile communication
radar communication » railway communication, today communications, risk communication
aided communication » risk communication, mobile communication
oral communication » grid communication, mobile communication, today communications

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: (( fiber-((((optic communication) OR (political communication))) OR (((radar communication) OR (aided communication)))) ) OR ( fiber-oral communication ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( fiber-((((optic communication) OR (political communication))) or (((radar communication) or (aided communication)))) ) or ( fiber-oral communication ))~".
• Adding a wildcard symbol may retrieve word variants: (( fiber-((((optic communication) OR (political communication))) or (((radar communication) or (aided communication)))) ) or ( fiber-oral communication ))*.