There were only a few.
From this alone, Nan Hua could guess that they should have determined the direction to find the person who came back then. There might be some DNA traces or other traces that they have found.
These few people they selected would be tested specifically to determine which one among them would be the one who was the culprit.
As for why they didn't find one person directly…
Either the evidence was inconclusive or the other person was actually disguising as other people among the students.
These were Nan Hua's thoughts.
She didn't know the details and had no interest to go and question them. Her current position didn't allow her to intervene with their decision no matter what it was.
"Are you interested in this matter?" Nan Xian Tang asked and looked at his cousin quietly. He knew that Nan Hua was not a person who liked to meddle in other people's business, but he felt that she should have a reason for asking this.
