Perhaps you should try some spelling variations:
"modified oxygen evolutionary algorithm" » "modified oxygen evolution algorithm", "modified oxygen solution algorithm"
"modified multiobjective optimization algorithm" » "modified multiobjective optimization algorithms", "modified multiobjective optimisation algorithm", "modified multiobjective estimation 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 oxygen evolutionary algorithm") OR ("modified multiobjective optimization algorithm"))~.
• Removing quotes may allow a broader search: (( modified oxygen evolutionary algorithm ) or ( modified multiobjective optimization algorithm ))~.
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