Perhaps you should try some spelling variations:
"modified churn prediction algorithm" » "modified churn predation algorithm", "modified churn predators algorithm", "modified cliff prediction algorithm", "modified fire prediction algorithm"
"modified notion approximation algorithms" » "modified network approximation algorithms", "modified time approximation algorithms", "modified one approximation 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 churn prediction algorithm") OR ("modified notion approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified churn prediction algorithm ) or ( modified notion approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified churn prediction algorithm") or ("modified notion approximation algorithms"))*.