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

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• Performing a fuzzy search may retrieve terms with similar spellings: (("modified multiobjective approximation algorithms") OR ("modified df estimation algorithms"))~.
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