Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithms" » "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithms", "modified multiobjective optimized algorithms"
"mapping learning estimation algorithm" » "mapping learning emotion algorithm", "mapping lighting estimation algorithm", "machine learning estimation algorithm", "enabling learning estimation algorithm"

Try widening your search to All Fields.

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 algorithms") or ("mapping learning estimation algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified multiobjective optimization algorithms") OR ("mapping learning estimation algorithm")).
• Removing quotes may allow a broader search: (( modified multiobjective optimization algorithms ) or ( mapping learning estimation algorithm )).
• Adding a wildcard symbol may retrieve word variants: (("modified multiobjective optimization algorithms") or ("mapping learning estimation algorithm"))*.