Perhaps you should try some spelling variations:
communication prevention » communication presentation, communication presenting, communication prediction
diagnosis dimension » diagnosis dispersion, diagnosis extension, diagnosis dimensionality
diagnosis session » diagnosis decision, diagnosis dispersion, diagnosis extension
a spaces » a space, 2 spaces, 4 spaces

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

• If you are trying to use Boolean operators, they must be ALL CAPS: communication prevention ((diagnosis dimension) OR (diagnosis session)) a spaces~.
• Adding a wildcard symbol may retrieve word variants: communication prevention ((diagnosis dimension) or (diagnosis session)) a spaces*.