Perhaps you should try some spelling variations:
"defined network optimization algorithms" » "defined network optimisation algorithm", "defined network estimation algorithms", "defined network estimation algorithm", "designed network optimization algorithms"
"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"

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"defined network optimization algorithms\") OR (\"modified one approximation algorithm\"))~".
• Removing quotes may allow a broader search: (( defined network optimization algorithms ) OR ( modified one approximation algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("defined network optimization algorithms") OR ("modified one approximation algorithm"))*.