Perhaps you should try some spelling variations:
"modified multiobjective optimisation algorithm" » "modified multiobjective optimization algorithm", "modified objective optimization algorithm", "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective estimation algorithms"
"modified over approximation algorithms" » "modified one approximation algorithms", "modified average approximation algorithms", "modified _ approximation algorithms", "modified near approximation algorithms", "modified orca approximation algorithms"

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