Perhaps you should try some spelling variations:
"modified policy optimization algorithms" » "modified policy optimisation algorithm", "modified policy estimation algorithms", "modified policy estimation algorithm", "modified policy optimisation algorithms", "modified policy estimation algorithmss", "modified topology optimization algorithms"
"modified multiobjective optimization algorithm" » "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithm", "modified multiobjective estimation algorithms"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified multiobjective optimization algorithm") or ("modified policy optimization algorithms"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified multiobjective optimization algorithm") OR ("modified policy optimization algorithms")).
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