Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithms" » "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithms", "modified multiobjective estimation algorithm"
"mapping learning method algorithm" » "machine learning method algorithm", "enabling learning method algorithm", "mapping learning mom algorithm", "mapping learning methods algorithm", "mapping graining methods algorithm", "mapping learning emotion algorithm"

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"modified multiobjective optimization algorithms\") OR (\"mapping learning method algorithm\"))~".
• Removing quotes may allow a broader search: (( modified multiobjective optimization algorithms ) OR ( mapping learning method algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified multiobjective optimization algorithms") OR ("mapping learning method algorithm"))*.