They went around the Amazon rainforest but did not manage to find the old man who saved Mu Ying back then, so they went back to Min City.
Mu Ying was saved by the old man shortly after she was left in the Amazon jungle. If it had not been the old man, Mu Ying probably would not have been able to survive six months there based on her abilities.
Yun Jian, on the other hand, had stayed alive for all six months based on her own capabilities. Compared to Yun Jian, Mu Ying was honestly a little weaker. It was also evident that Yun Jian was an unprecedented case for surviving in Amazonia for six months at her age that time.
Mu Ying was thankful to the old man for saving her back then. It was just that she could not find him after going around the jungle and nearly flipping the ground over. She could only relent and return to Min City.
While Mu Ying went back to Min City, Yun Jian went back to Longmen City. Berserk Dragon followed Mu Ying to Min City.