Perhaps you should try some spelling variations:
"modified co evolutionary algorithm" » "modified co evolution algorithm", "modified co solution algorithm", "modified _ evolutionary algorithm", "modified df evolutionary algorithm", "modified orca evolutionary algorithm"
"modified coverage approximation algorithms" » "modified average approximation algorithms", "modified _verage approximation algorithms", "modified dfverage approximation algorithms", "modified orcaverage approximation algorithms"

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified co evolutionary algorithm") OR ("modified coverage approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified co evolutionary algorithm ) or ( modified coverage approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified co evolutionary algorithm") or ("modified coverage approximation algorithms"))*.