Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithm" » "modified multiobjective optimization algorithms", "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithm"
"enabling learning emotion algorithm" » "mapping learning emotion algorithm", "enabling learning evolution algorithm", "enabling learning estimation algorithm", "enabling learning predation algorithm", "enabling learning method 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 algorithm") or ("enabling learning emotion algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified multiobjective optimization algorithm") OR ("enabling learning emotion algorithm")).
• Removing quotes may allow a broader search: (( modified multiobjective optimization algorithm ) or ( enabling learning emotion algorithm )).
• Adding a wildcard symbol may retrieve word variants: (("modified multiobjective optimization algorithm") or ("enabling learning emotion algorithm"))*.