Perhaps you should try some spelling variations:
optimization algorithm » optimization algorithms, optimisation algorithm, estimation algorithm
dose approximation » one approximation, _ approximation, rough approximations
time approximation » one approximation, _ 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: (( ((dose approximation) OR (time approximation)) algorithms ) OR ( qoe optimization algorithm ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((dose approximation) OR (time approximation)) algorithms ) or ( qoe optimization algorithm ))~".
• Adding a wildcard symbol may retrieve word variants: (( ((dose approximation) OR (time approximation)) algorithms ) or ( qoe optimization algorithm ))*.