Perhaps you should try some spelling variations:
"routledge telecommunication sector." » "routledge communication sector.", "contents telecommunication sector.", "routledge telecommunications sector.", "routledge telecommunication systems.", "routledge telecommunication services."
"mobile telecommunication system." » "mobile communication system.", "mobile communications system.", "rural telecommunications system.", "mobile telecommunication systems.", "mobile telecommunication services.", "mobile telecommunication union."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("mobile telecommunication system.") or ("routledge telecommunication sector."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("mobile telecommunication system.") OR ("routledge telecommunication sector.")).
• Removing quotes may allow a broader search: (( mobile telecommunication system. ) or ( routledge telecommunication sector. )).
• Adding a wildcard symbol may retrieve word variants: (("mobile telecommunication system.") or ("routledge telecommunication sector."))*.