Perhaps you should try some spelling variations:
"modified coverage approximation algorithms" » "modified average approximation algorithms"
"modified traces evolution algorithm" » "modified traces solution algorithm", "modified traces evolutionary algorithm", "modified traces convolution algorithms", "modified sales evolution algorithm", "modified time evolution algorithm"

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 coverage approximation algorithms") OR ("modified traces evolution algorithm"))~.
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