Perhaps you should try some spelling variations:
"modified multiobjective approximation algorithms" » "modified multiobjective optimization algorithms"
"modified bi1 optimization algorithms" » "modified bi1 optimisation algorithm", "modified bi1 estimation algorithms", "modified bi1 estimation algorithm", "modified _ optimization algorithms", "modified qoe optimization algorithms", "modified game optimization algorithms"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified bi1 optimization algorithms") OR ("modified multiobjective approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified bi1 optimization algorithms ) or ( modified multiobjective approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified bi1 optimization algorithms") or ("modified multiobjective approximation algorithms"))*.