Perhaps you should try some spelling variations:
communications convention » communications connections, communication connection, communication conversation
communication conversion » communication conversation, communication cohesion, communication connection
dimension slides » dimension codes, dimension video, dimensions des
hat dimension » a dimension, tacit dimension, pit dimensions
titles » title

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((communication conversion) or (communications convention)) hat dimension slides titles~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((communication conversion) OR (communications convention)) hat dimension slides titles.
• Adding a wildcard symbol may retrieve word variants: ((communication conversion) or (communications convention)) hat dimension slides titles*.