Perhaps you should try some spelling variations:
"modified multiobjective estimation algorithms" » "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective optimisation algorithm"
"modified aging approximation algorithms" » "modified one approximation algorithms", "modified time approximation algorithms", "modified average approximation algorithms", "modified caging approximation algorithms"

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