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

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("defined network optimisation algorithm") or ("modified coverage approximation algorithms"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("defined network optimisation algorithm") OR ("modified coverage approximation algorithms"))*.
• Removing quotes may allow a broader search: (( defined network optimisation algorithm ) or ( modified coverage approximation algorithms ))*.