Some Chinese sentences may appear to have two subjects:
1. xiàng bízi cháng
elephant nose long
Elephants’ noses are long. / Elephants have long noses. (Li & Thompson 1989, p. 92)
In (1), there seems to be two subjects, xiàng and bízi. But xiàng is actually not a subject, it is a topic (what the sentence is about). And the remaining part of the sentence is a comment (the description of the topic), where bízi is the subject. The relationship between the topic (xiàng) and the subject (bízi) is a part-whole relationship, where bízi is a part of xiàng.
References
Li, C. N., & Thompson, S. A. (1989). Mandarin Chinese: A functional reference grammar. Univ of California Press.