From Longman Dictionary of Contemporary Englishnot want to knownot want to knowBritish English informalREFUSE to not be interested in someone and what they want to say She’d approached several model agencies but they just didn’t want to know. → know
Examples from the Corpus
not want to know• You'd think the government would be concerned about people sleeping rough, but they just don't want to know.• I did not want to know.• The employers, although they are expected to contribute, do not want to know.• Whatever it was, Lisa did not want to know.• If you're going to start an argument with Alex I don't want to know about it.• She never asked because she did not want to know if they all had to be burned.• And accustomed now to not knowing why, did not want to know it.• Holmes did not want to know too much about the people in his cases.• I did not want to know what was going on in the world. 