Perhaps you should try some spelling variations:
communication communications » communication communication, communication communicating, communications communication
communications hat » communications what, communications a, communications how
hat dimension » a dimension, tacit dimension, pit dimensions
range spaces » gauge spaces, range states, large spaces
tuple spaces » tuple space, type spaces, triple space
safe spaces » state spaces, shape spaces, scale spaces

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

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