Perhaps you should try some spelling variations:
"modified notion approximation algorithms" » "modified network approximation algorithms", "modified time approximation algorithms", "modified one approximation algorithms"
"modified elements evolution algorithm" » "modified elements solution algorithm", "modified elements evolutionary algorithm", "modified elements convolution 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 elements evolution algorithm") OR ("modified notion approximation algorithms"))~.
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