The meaning of these two sentences is that her vague appearance is like clouds gently covering the moon, and her image is wandering like swirling snowflakes blown by the flowing wind.
Source:
These two sentences are poems describing the appearance of the goddess Luoshui. It comes from "Ode to the Goddess of Luo" written by Cao Zhi during the Three Kingdoms period.
Original poem:
I told him: "Its shape is as graceful as a startled giant, and as graceful as a swimming dragon. The glory of the autumn chrysanthemums, the luxuriant spring pine trees. It seems as if it is as light as the sky. The clouds cover the moon, and it flutters like snow in the flowing wind.
Translation:
I told him: "Her figure is as graceful as a flying geese, as graceful as a swimming bird." The moving dragon. Her face is as radiant as a chrysanthemum in the autumn sun, and her body is as lush as a green pine in the spring breeze. Her vague appearance is like clouds gently covering the moon, and her image is wandering like swirling snowflakes blown by the wind.
Creative background
"Luo Shen Fu" is a famous poem written by Cao Zhi during the Three Kingdoms period. Cao Zhi imitated the description of the Wushan goddess in "Ode to the Goddess" by Song Yu of the Chu State during the Warring States Period, and narrated the story of his encounter with the Luo Shen by the Luoshui River. This poem fictionalizes the author's encounter with Luo Shen and their longing and love for each other. The image of Luo Shen is extremely beautiful, the love between man and god is ethereal and blurred, and finally expresses the infinite sadness and melancholy.
Luo Shen, also known as Mi Fei, is a goddess in myths and legends in ancient China. She is the daughter of the Fuxi family. She came to the world and came to Luoyang because she was infatuated with the beautiful scenery on both sides of the Luo River. Cao Zhi's "Luo Shen Fu" is a famous poem describing her through the ages. The "Xiao Kuang" chapter in Volume 311 of "Taiping Guangji" and the "Legend" chapter in Volume 32 of "Leishu" record an affair between Xiao Kuang and the Luo Goddess.
My personal understanding of these two sentences.
The first sentence describes the appearance: vaguely seen like clouds covering the moon, similar to holding a pipa and half covering the face.
The second sentence, descriptive form: like snowflakes blown by the wind, one word to describe it is graceful