Perhaps you should try some spelling variations:
communications communication » communication communication, communicating communication, communication communicating
extension development » hypertension development, detection development, lesion development
extension developing » extensions developing, expression developing, dimensions developing
communication fast » telecommunication fast

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 fast ((extension developing) or (extension development)) lung~.
• If you are trying to use Boolean operators, they must be ALL CAPS: communications communication fast ((extension developing) OR (extension development)) lung.
• Adding a wildcard symbol may retrieve word variants: communications communication fast ((extension developing) or (extension development)) lung*.