Perhaps you should try some spelling variations:
"modified co evolution algorithm" » "modified co solution algorithm", "modified co evolutionary algorithm", "modified co convolution algorithms", "modified _ evolution algorithm", "modified df evolution algorithm", "modified orca evolution algorithm"
"modified complexity approximation algorithms" » "modified _mplexity approximation algorithms", "modified dfmplexity approximation algorithms", "modified orcamplexity 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 evolution algorithm") OR ("modified complexity approximation algorithms"))~.
• Removing quotes may allow a broader search: (( modified co evolution algorithm ) or ( modified complexity approximation algorithms ))~.
• Adding a wildcard symbol may retrieve word variants: (("modified co evolution algorithm") or ("modified complexity approximation algorithms"))*.