Perhaps you should try some spelling variations:
"modified parameter optimization algorithms" » "modified parameter optimisation algorithm", "modified parameter estimation algorithms", "modified parameter estimation algorithm", "modified parameters optimization algorithms"
"designed network approximation algorithms" » "defined network 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: (("designed network approximation algorithms") OR ("modified parameter optimization algorithms"))~.
• Removing quotes may allow a broader search: (( designed network approximation algorithms ) or ( modified parameter optimization algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("designed network approximation algorithms") or ("modified parameter optimization algorithms"))*.