C1621 How to Investigate

"Then how can we investigate?" "What should we do?" Zhao Dajian said.

"I think it's very difficult. Since that person wants to do this, he must have made sufficient preparations to prevent others from investigating." Cao Lee said.

I nodded my head, "Yes, but since Secretary Sun wants to check, then I will really check it out. It's just that I don't know where to start looking for it myself