Perhaps you should try some spelling variations:
"modified response approximation algorithms" » "modified one approximation algorithms", "modified response association algorithms"
"modified bayesian optimization algorithm" » "modified bayesian optimization algorithms", "modified bayesian optimisation algorithm", "modified bayesian estimation algorithm"

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• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified response approximation algorithms") OR ("modified bayesian optimization algorithm"))~.
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