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

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

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