Perhaps you should try some spelling variations:
communication conversations » communication conversation, communication cooperation, communication constructions
conversations basic » conversations basics, conversation basic, conversational basis
extension session » extensions session, extension region, extension lessons
expansion session » expression session, expansion semi, expansions decisions

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

• Performing a fuzzy search may retrieve terms with similar spellings: communication conversations basic ((extension session) OR (expansion session)) general~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "communication conversations basic ((extension session) OR (expansion session)) general".
• Adding a wildcard symbol may retrieve word variants: communication conversations basic ((extension session) OR (expansion session)) general*.