Perhaps you should try some spelling variations:
"modified multiobjective estimation algorithms" » "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective optimisation algorithm"
"modified orca predation algorithm" » "modified orca predators algorithm", "modified orca estimation algorithm", "modified dorca predation algorithm", "modified orcad predation algorithm", "modified ohca predation algorithm"

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