Perhaps you should try some spelling variations:
"modified sphere optimisation algorithm" » "modified sphere optimization algorithms", "modified sphere estimation algorithm", "modified sphere estimation algorithms"
"modified notion approximation algorithms" » "modified network approximation algorithms", "modified time approximation algorithms", "modified one 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: (("modified sphere optimisation algorithm") OR ("modified notion approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified sphere optimisation algorithm ) or ( modified notion approximation algorithms ))~.
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