Theoretically speaking, after a person passes through a place, their skin cells will be left behind on the traces they passed.
As long as these skin cells can be collected, the other party's DNA information can be locked down.
Of course, in reality, determining this kind of spatial trace is not easy, because the quantity of skin cells is too small, and current technology cannot conduct DNA identification; only large pieces of skin or hair can be subjected to DNA identification in this regard.
"Let's start from the side where the killer shouldered the corpse. The opponent, burdened by the body, probably left something behind."
"Also, check the clothes of the corpse, especially the front of the clothing, as something might have been left when the body was carried."
The reason Lu Chuan determined that the perpetrator shouldered the body instead of cradling it was because of the different footprints on the fallen leaves.
