Perhaps you should try some spelling variations:
"modified notion approximation algorithms" » "modified network approximation algorithms", "modified time approximation algorithms", "modified one approximation algorithms"
"model learning evolution algorithm" » "model learning solution algorithm", "model learning evolutionary algorithm", "model learning convolution algorithms", "model learning convolution algorithm", "model learning emotion algorithm", "mobile learning evolution algorithm"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("model learning evolution algorithm") or ("modified notion approximation algorithms"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("model learning evolution algorithm") OR ("modified notion approximation algorithms")).
• Removing quotes may allow a broader search: (( model learning evolution algorithm ) or ( modified notion approximation algorithms )).
• Adding a wildcard symbol may retrieve word variants: (("model learning evolution algorithm") or ("modified notion approximation algorithms"))*.