"How did you think of lifting her bed board?" The murder victim had both hands cuffed together, how would she be able to leave any evidence? Moreover, the killer definitely would not have given her time to do so.
"I saw scratch marks when I lifted the pillow," Xu Lan took out a magnifying glass to pass to Sun Fei and pointed at the position of the scratch marks calmly.
Sun Fei took the magnifying glass and saw fingernail scratch marks on the bed board.
...
It was not well-defined, but enough to be recognized as a hint. Immediately, Sun Fei drew it onto the notebook that he always carried around. Then, he stood up and patted Xu Lan's shoulder.
"You did well. Hey, where's Officer Li?" he asked, realizing that he did not see Li Xiu after entering the place for quite some time.
"He went out to buy water. I'll give him a call," mentioned Xu Lan.
