Perhaps you should try some spelling variations:
approximation algorithm » approximation algorithms
optimization algorithm » optimization algorithms, optimisation algorithm, estimation algorithm
market optimization » game optimization, parameter optimization, market capitalization
time approximation » one approximation, _ approximation

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: (( market optimization algorithm ) OR ( time approximation algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (( market optimization algorithm ) or ( time approximation algorithm ))*.