Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithms" » "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithms", "modified multiobjective optimized algorithms"
"modified invasive estimation algorithm" » "modified invasive ventilation algorithm", "modified passive estimation algorithm"

You may be able to get more results by adjusting your search query.

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• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified invasive estimation algorithm") OR ("modified multiobjective optimization algorithms")).
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