Perhaps you should try some spelling variations:
"modified df optimisation algorithmssss" » "modified df optimisation algorithm", "modified _ optimisation algorithmssss", "modified _ optimization algorithmssss", "modified qoe optimization algorithmssss", "modified adam optimisation algorithmssss", "modified bi1 optimisation algorithmssss"
"modified multiobjective optimization algorithms" » "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithms", "modified multiobjective estimation algorithm"

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