expression
hide a leaf in a forest
Proverb meaning the best way to hide something is to place it among similar things, making it inconspicuous.
木の葉を隠すなら森の中というように、小さな嘘も大きな話の中に紛れ込ませればバレにくい。
As the saying goes, 'If you want to hide a leaf, put it in a forest' — even a small lie is hard to detect if you mix it into a big story.
A Japanese proverb; the exact origin is uncertain, but it reflects a common folk wisdom about camouflage and blending in.