Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithm" » "modified multiobjective optimization algorithms", "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithm"
"modified optimal solution algorithm" » "modified optimal evolution algorithm", "modified optimal convolution algorithms", "modified optimal evolutionary algorithm", "modified thermal solution 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 algorithm\") OR (\"modified optimal solution algorithm\"))~".
• Removing quotes may allow a broader search: (( modified multiobjective optimization algorithm ) OR ( modified optimal solution algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified multiobjective optimization algorithm") OR ("modified optimal solution algorithm"))*.