Perhaps you should try some spelling variations:
"modified network approximation algorithm" » "modified network approximation algorithms", "certified network approximation algorithm", "defined network approximation algorithm", "modified near approximation algorithm"
"modified passive optimization algorithms" » "modified passive optimisation algorithm", "modified passive estimation algorithms", "modified passive estimation algorithm", "modified bayesian optimization algorithms", "modified game optimization algorithms", "modified policy optimization algorithms", "modified adaptive optimization algorithms"

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