Perhaps you should try some spelling variations:
"modified multiobjective optimization algorithms" » "modified multiobjective optimisation algorithm", "modified multiobjective estimation algorithms", "modified multiobjective optimized algorithms"
"modified bi1 estimation algorithm" » "modified risk estimation algorithm", "modified _ estimation 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 bi1 estimation algorithm\") OR (\"modified multiobjective optimization algorithms\"))~".
• Removing quotes may allow a broader search: (( modified bi1 estimation algorithm ) OR ( modified multiobjective optimization algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified bi1 estimation algorithm") OR ("modified multiobjective optimization algorithms"))*.