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

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