Perhaps you should try some spelling variations:
"modified notion approximation algorithms" » "modified network approximation algorithms", "modified time approximation algorithms", "modified one approximation algorithms"
"mobile learning via algorithm" » "machine learning via algorithm", "mobile learning adam algorithm", "mobile learning _ algorithm", "mobile learning mom algorithm", "mobile learning a algorithm", "mobile learning video algorithm", "mobile learning data 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: (("mobile learning via algorithm") OR ("modified notion approximation algorithms"))~.
• Removing quotes may allow a broader search: (( mobile learning via algorithm ) or ( modified notion approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("mobile learning via algorithm") or ("modified notion approximation algorithms"))*.