Perhaps you should try some spelling variations:
"modified coverage approximation algorithms" » "modified average approximation algorithms"
"modified passive solution algorithms" » "modified passive solution algorithm", "modified passive evolution algorithm", "modified passive convolution algorithms", "modified adaptive solution algorithms", "modified positive solutions algorithms", "modified saline solution 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 passive solution algorithms") OR ("modified coverage approximation algorithms"))~.
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