beneath the/someone's radar idiom
被忘记，被忽视
ignored or not noticed by someone or by people in general
For the first 8 years of its existence, the band stayed largely beneath the radar. 在乐队成立的前八年里，他们大部分时间都被人忽略。
Little local bars like this fly beneath the tourists' radar. 像这样的当地小酒吧一般都不会引起游客的注意。