Perhaps you should try some spelling variations:
"modified df optimization algorithmssssssss" » "modified df optimization algorithms", "modified _ optimization algorithmssssssss", "modified qoe optimization algorithmssssssss", "modified _ optimisation algorithmssssssss", "modified adam optimization algorithmssssssss", "modified bi1 optimization algorithmssssssss"
"modified objective allocation algorithms" » "modified objective estimation algorithms", "modified objective approximation algorithms"

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