Perhaps you should try some spelling variations:
"modified one approximation algorithm" » "modified one approximation algorithms", "modified time approximation algorithm", "modified _ approximation algorithm", "modified rough approximations algorithm", "modified male approximation algorithm", "modified near approximation algorithm", "modified orca approximation algorithm"
"machines making methods algorithm" » "machines using methods algorithm", "machines learning methods algorithm", "machines graining methods 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: (("machines making methods algorithm") OR ("modified one approximation algorithm"))~.
• Removing quotes may allow a broader search: (( machines making methods algorithm ) or ( modified one approximation algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("machines making methods algorithm") or ("modified one approximation algorithm"))*.