Perhaps you should try some spelling variations:
"modified objective optimization algorithmss" » "modified objective optimization algorithms", "modified objective estimation algorithms", "modified objective estimation algorithm", "modified multiobjective optimization algorithmss"
"modified passive optimisation algorithm" » "modified passive optimization algorithms", "modified passive estimation algorithm", "modified passive estimation algorithms", "modified adaptive optimisation algorithm"

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• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified passive optimisation algorithm") OR ("modified objective optimization algorithmss"))~.
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