Perhaps you should try some spelling variations:
"modified multiobjective estimation algorithms" » "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective optimisation algorithm"
"modified df evolution algorithm" » "modified df solution algorithm", "modified df evolutionary algorithm", "modified df convolution algorithms", "modified _ evolution algorithm", "modified co evolution algorithm", "modified adam evolution algorithm", "modified bi1 evolution algorithm"

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