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

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