Perhaps you should try some spelling variations:
"modified coverage approximation algorithms" » "modified average approximation algorithms"
"modified thermal protection algorithm" » "modified thermal predation algorithm", "modified thermal evolution algorithm", "modified thermal solution algorithm", "modified thermal properties algorithm", "modified animal protection algorithm", "modified human protection 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 thermal protection algorithm"))~.
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