Perhaps you should try some spelling variations:
"modified _ optimization algorithmssssssss" » "modified _ optimization algorithms", "modified _ optimization algorithmsssssssss", "modified _ optimisation algorithmssssssss", "modified _ estimation algorithmssssssss"
"modified objective optimization algorithm" » "modified multiobjective optimization algorithm", "modified objective optimization algorithms", "modified objective optimisation algorithm", "modified objective estimation algorithm"

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