Perhaps you should try some spelling variations:
"optimization algorithmss" » "optimisation algorithm", "estimation algorithm", "optimized algorithms", "optimisation algorithms", "estimation algorithms", "optimized algorithmss"
"optimization algorithms" » "optimisation algorithm", "estimation algorithm", "optimized algorithms"
"estimation algorithms" » "estimation algorithm", "optimisation algorithm", "approximation algorithms"

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: (("estimation algorithms") OR ((("optimization algorithmss") OR ("optimization algorithms"))))~.
• Removing quotes may allow a broader search: (( estimation algorithms ) or ((( optimization algorithmss ) or ( optimization algorithms ))))~.
• Adding a wildcard symbol may retrieve word variants: (("estimation algorithms") or ((("optimization algorithmss") or ("optimization algorithms"))))*.