Perhaps you should try some spelling variations:
"modified notion approximation algorithms" » "modified network approximation algorithms", "modified time approximation algorithms", "modified one approximation algorithms"
"modified learning emotion algorithms" » "modified learning estimation algorithms", "modified learning evolution algorithm", "modified learning vision algorithms", "mobile learning emotion algorithms", "modified caging emotion algorithms", "modified learning method 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 learning emotion algorithms") OR ("modified notion approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified learning emotion algorithms ) or ( modified notion approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified learning emotion algorithms") or ("modified notion approximation algorithms"))*.