I believe there are many Nishuihan users who don’t know the guide for Nishuihan mobile game Sword Rain, Dao Frost Adventure. Next is the "Nishuihan Mobile Game Sword Rain, Sword Frost Adventure Strategy Guide" written by the editor of Source Code.com. Interested students, please take a look. It may help you.
Unlock method: Breath-Martial Arts Adventure-Sword Rain, Knife Frost
1. Go to Yunqi Bamboo Trail and interact with the light spots here.
2. Then jump to the mountain and watch the two people fighting in front of you.
3. Then jump down and have a conversation with the two.
4. Then fight with the two.
5. After the conversation is over and the internal skills are transferred, follow the prompts to find the sword art.
6. Once found, the task can be completed.
These contents are summarized from the fact sheet, and I believe they can answer your questions on this issue. This website also has more high-quality guides about Nishuihan mobile game, you are welcome to check it out at any time.