1. The ancestors and relatives of disciple himself and his spouse in previous lives. Some immortals are not easy for people to see. They don't trust people, so some will hide.
2. Foreign aid invited by Xianjia. Usually, such Qing immortals have certain abilities, such as being proficient in divination and astrology, studying Feng Shui, and being too fragrant to have offspring. Such a clear fairy is of great help to Tang Kou's ability to see things.
This happened by accident. I just accidentally got caught. Usually, this kind of immortal is brought back by disciples when they go to famous mountains and rivers or temples.