Perhaps you should try some spelling variations:
"modified objective estimation algorithms" » "modified objective estimation algorithm", "modified objective optimization algorithms", "modified objective optimisation algorithm", "modified objective allocation algorithms"
"mobile learning convolution algorithm" » "mobile learning convolution algorithms", "mobile learning evolution algorithm", "mobile learning solution algorithm", "machine learning convolution algorithm"

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 objective estimation algorithms") OR ("mobile learning convolution algorithm"))~.
• Removing quotes may allow a broader search: (( modified objective estimation algorithms ) or ( mobile learning convolution algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified objective estimation algorithms") or ("mobile learning convolution algorithm"))*.