C1551 Observation Minute Subtlety

"Uh... I'm afraid the professor will be disappointed. The other party's technique is very professional. We have already extracted the fingerprints on the door handle, but we found nothing. " Although he didn't want to admit it, Chen Loong had to admit it. They did not find any useful clues.

The only thing he found was the fat factory director in front of him.

"What about him?"

"Lu Zhiqiang