Perhaps you should try some spelling variations:
"modified response optimization algorithm" » "modified response optimization algorithms", "modified response optimisation algorithm", "modified response estimation algorithms"
"modified parameters estimation algorithm" » "modified parameter estimation algorithm", "modified parameter estimates algorithm", "modified parameter optimization algorithm"

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified parameters estimation algorithm") or ("modified response optimization algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified parameters estimation algorithm") OR ("modified response optimization algorithm")).
• Removing quotes may allow a broader search: (( modified parameters estimation algorithm ) or ( modified response optimization algorithm )).
• Adding a wildcard symbol may retrieve word variants: (("modified parameters estimation algorithm") or ("modified response optimization algorithm"))*.