Perhaps you should try some spelling variations:
optimisation algorithms » optimization algorithms, estimation algorithms, estimation algorithm
optimisation algorithm » optimization algorithms, estimation algorithm, estimation algorithms
sphere optimisation » sphere estimation
_ optimisation » _ optimization

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( sphere optimisation algorithms ) or ( _ optimisation algorithm ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( sphere optimisation algorithms ) OR ( _ optimisation algorithm ))*.