Perhaps you should try some spelling variations:
"modified allocation approximation algorithms" » "modified allocation optimization algorithms"
"modified network optimization algorithm" » "modified network optimization algorithms", "modified network optimisation algorithm", "modified network estimation algorithm", "certified network optimization algorithm", "defined network optimization algorithm", "modified near optimization algorithm"

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• Performing a fuzzy search may retrieve terms with similar spellings: (("modified allocation approximation algorithms") OR ("modified network optimization algorithm"))~.
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