Perhaps you should try some spelling variations:
optimization algorithmss » optimization algorithms, optimisation algorithm, estimation algorithms
risk optimization » robust optimization, _ optimization, risk estimation
game optimization » stage optimization, market optimization, _ optimization
qoe optimization » _ optimization, stage optimization, _ optimisation

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( ((risk optimization) OR (qoe optimization)) algorithms ) or ( game optimization algorithmss ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ((risk optimization) OR (qoe optimization)) algorithms ) OR ( game optimization algorithmss )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((risk optimization) OR (qoe optimization)) algorithms ) or ( game optimization algorithmss ))".
• Adding a wildcard symbol may retrieve word variants: (( ((risk optimization) OR (qoe optimization)) algorithms ) or ( game optimization algorithmss ))*.