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 orca predation algorithm" » "modified orca predators algorithm", "modified orca estimation algorithm", "modified dorca predation algorithm", "modified orcad predation algorithm", "modified ohca predation algorithm"

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 objective optimization algorithms") OR ("modified orca predation algorithm"))~.
• Removing quotes may allow a broader search: (( modified objective optimization algorithms ) or ( modified orca predation algorithm ))~.
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