lái wú yǐng , qù wú zōng
lit. come without a shadow, leave without a footprint (idiom); to come and go without a trace
来
lái
to come
无
wú
not to have
影
yǐng
picture
,
,
去
qù
to go
踪
zōng
variant of 蹤|踪[zong1]