Perhaps you should try some spelling variations:
"modified notion approximation algorithms" » "modified network approximation algorithms", "modified time approximation algorithms", "modified one approximation algorithms"
"modified markets selecting algorithm" » "modified markets splitting algorithm", "modified markets scheduling algorithm", "modified market selection algorithm", "modified male selecting 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 markets selecting algorithm") OR ("modified notion approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified markets selecting algorithm ) or ( modified notion approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified markets selecting algorithm") or ("modified notion approximation algorithms"))*.