As Dong Tianyu said, stumbling upon a cultivation method and successfully practicing it all by yourself is not impossible, it's just extremely improbable.
Observation is the first step of the compulsory courses in traditional Chinese medicine. Through the observation of Dong Tianyu's Essence, Qi, and Spirit, Dr. Zuo had known that Dong Tianyu was not just a martial artist, but a master stronger than himself. There was no way Dong Tianyu was just practicing casually as he claimed.
However, thinking about how the Officials invited him to join their organization after confirming his acquisition of Inner Strength, he found Robinson William's name on the member list of the West City District. Moreover, he was even appointed as the Command Post leader in the West City District.