Perhaps you should try some spelling variations:
approximations algorithm » approximation algorithm, approximation algorithms
optimization algorithms » optimisation algorithm, estimation algorithms, estimation algorithm
rough approximations » one approximation
qoe optimization » game optimization, _ optimization, stage optimization

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: (( rough approximations algorithm ) OR ( qoe optimization algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (( rough approximations algorithm ) or ( qoe optimization algorithms ))*.