Perhaps you should try some spelling variations:
"modified robust estimation algorithms" » "modified robust estimation algorithm", "modified robust optimization algorithms", "modified robust optimisation algorithm", "modified pose estimation algorithms", "modified risk estimation algorithms"
"modified learning convolution algorithm" » "modified learning convolution algorithms", "modified learning evolution algorithm", "modified learning solution algorithm", "mobile learning convolution algorithm", "modified caging convolution 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 robust estimation algorithms") or ("modified learning convolution algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified robust estimation algorithms") OR ("modified learning convolution algorithm")).
• Removing quotes may allow a broader search: (( modified robust estimation algorithms ) or ( modified learning convolution algorithm )).
• Adding a wildcard symbol may retrieve word variants: (("modified robust estimation algorithms") or ("modified learning convolution algorithm"))*.