Perhaps you should try some spelling variations:
communication context » communication contexts, communication content, communicative context
based extraction » based interaction, phase extraction, based education
context based » content based
using spatio » using spatial, using static
using sparse » using spss

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

• Performing a fuzzy search may retrieve terms with similar spellings: communication context based extraction ((((using spatio) or (using sparse))) or (using stochastic))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: communication context based extraction ((((using spatio) OR (using sparse))) OR (using stochastic)).
• Adding a wildcard symbol may retrieve word variants: communication context based extraction ((((using spatio) or (using sparse))) or (using stochastic))*.