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"
"designed network optimization algorithms" » "designed network optimisation algorithm", "designed network estimation algorithms", "designed network estimation algorithm", "defined network optimization algorithms"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("designed network optimization algorithms") or ("modified one approximation algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("designed network optimization algorithms") OR ("modified one approximation algorithm")).
• Removing quotes may allow a broader search: (( designed network optimization algorithms ) or ( modified one approximation algorithm )).
• Adding a wildcard symbol may retrieve word variants: (("designed network optimization algorithms") or ("modified one approximation algorithm"))*.