What is "walking through the snow without trace" used to describe? Where did it come from?

The original meaning is to walk in the snow without leaving a trace, and it is extended to do something without leaving a trace.

Unknown source. Some people say that "walking through the snow without trace" is a master of lightness skill. Hua's nickname comes from the teacher's famous ballad Xiao Ba Yi. Some people say that it comes from "walking in the snow in the middle of the night, looking back at the seamless night, the moon is boundless, and Jinger has dyed her clothes." This poem.