Perhaps you should try some spelling variations:
communication concepts » communication circuits, communication congresses, communication channels
basics dimensions » basic dimensions, physics dimensions, based dimensions
concepts basics » concepts basic, concepts tactics, concepts based
regression line » regression lines, regression splines, regression case

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 concepts basics dimensions ((regression line) OR (regression linear))~.
• Adding a wildcard symbol may retrieve word variants: communication concepts basics dimensions ((regression line) or (regression linear))*.