Perhaps you should try some spelling variations:
"modified network optimization algorithm" » "modified network optimization algorithms", "modified network optimisation algorithm", "modified network estimation algorithm", "certified network optimization algorithm", "defined network optimization algorithm", "modified near optimization algorithm"
"modified rough approximation algorithms" » "modified rough approximations algorithms", "modified one approximation algorithms"

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: "((\"modified rough approximation algorithms\") OR (\"modified network optimization algorithm\"))~".
• Removing quotes may allow a broader search: (( modified rough approximation algorithms ) OR ( modified network optimization algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified rough approximation algorithms") OR ("modified network optimization algorithm"))*.