Perhaps you should try some spelling variations:
"modified multiobjective estimation algorithms" » "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective optimisation algorithm"
"modified one approximation algorithms" » "modified time approximation algorithms", "modified _ approximation algorithms", "modified rough approximations algorithms", "modified male approximation algorithms", "modified near approximation algorithms", "modified orca approximation algorithms"

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