Perhaps you should try some spelling variations:
"modified multiobjective estimation algorithms" » "modified multiobjective optimization algorithms", "modified multiobjective estimation algorithm", "modified multiobjective optimisation algorithm"
"modified pulse approximation algorithms" » "modified one approximation algorithms", "modified time approximation algorithms", "modified male approximation algorithms", "modified passive approximation 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 pulse approximation algorithms") OR ("modified multiobjective estimation algorithms"))~.
• Removing quotes may allow a broader search: (( modified pulse approximation algorithms ) or ( modified multiobjective estimation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified pulse approximation algorithms") or ("modified multiobjective estimation algorithms"))*.