无心插柳 (無心插柳) wúxīn chā liǔ

wúxīn chā liǔ set phrase (of a good outcome) unanticipated; serendipitous; fortuitous
Domain: Idiom 成语
Notes: (CC-CEDICT '無心插柳')

Also contained in

无心插柳柳成阴有意栽花花不发,无心插柳柳成阴