Perhaps you should try some spelling variations:
"verified network approximation algorithm" » "verified network approximation algorithms", "certified network approximation algorithm", "defined network approximation algorithm"
"modified objective estimation algorithm" » "modified objective optimization algorithm", "modified objective allocation 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: "((\"modified objective estimation algorithm\") OR (\"verified network approximation algorithm\"))~".
• Removing quotes may allow a broader search: (( modified objective estimation algorithm ) OR ( verified network approximation algorithm ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified objective estimation algorithm") OR ("verified network approximation algorithm"))*.