Nianyang smiled slightly, "You may not understand this. Herbal medicine like Chuanwu, which is a slow-acting poison, is a non-prescription drug usually used in small amounts in traditional medicines to treat illnesses.
The quantity for four or five months is substantial. The pharmacy is afraid of incidents and won't dare to sell it all to them at once, so they must have bought it in different visits.
Because they frequently bought this special medicinal herb, the staff at the pharmacy will surely have a strong impression of him, and will record his name. He might even be caught on surveillance, making the security record solid evidence!
Luo Lanzhen and Luo Song marvel at Nianyang's orderly analysis. Luo Song asks, "This method sounds feasible, but how should we investigate it? I can't find any leads now!!"
