Perhaps you should try some spelling variations:
"modified coverage approximation algorithms" » "modified average approximation algorithms"
"modified mild evolutionary algorithm" » "modified mild evolution algorithm", "modified mild solution algorithm", "modified male evolutionary algorithm", "modified seird evolutionary algorithm", "modified bi1 evolutionary algorithm"

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• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"modified coverage approximation algorithms\") OR (\"modified mild evolutionary algorithm\"))~".
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