Perhaps you should try some spelling variations:
"modified objective optimization algorithms" » "modified objective optimisation algorithm", "modified objective estimation algorithms", "modified objective estimation algorithm", "modified multiobjective optimization algorithms"
"modified delphi evolutionary algorithm" » "modified delphi evolution algorithm", "modified delphi solution algorithm"

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• Performing a fuzzy search may retrieve terms with similar spellings: (("modified objective optimization algorithms") or ("modified delphi evolutionary algorithm"))~.
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