Perhaps you should try some spelling variations:
"modified sphere optimization algorithms" » "modified sphere optimisation algorithm", "modified sphere estimation algorithms", "modified sphere estimation algorithm", "modified stage optimization algorithms", "modified response optimization algorithms"
"modified objective predators algorithm" » "modified objective predation algorithm"

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 objective predators algorithm") OR ("modified sphere optimization algorithms"))~.
• Removing quotes may allow a broader search: (( modified objective predators algorithm ) or ( modified sphere optimization algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified objective predators algorithm") or ("modified sphere optimization algorithms"))*.