It means: there is still a long way to go in the pursuit of truth (true knowledge), but I will persevere and spare no effort to pursue and explore.
I think the "repair" here should be interpreted as: (road) long.
Judging from the text, "Xiu Yuan" should be a coordinate word, corresponding to "Qiu" in the next sentence.
Li Sao is Qu Yuan's masterpiece. Qu Yuan's illness, Chu Huaiwang's refusal to listen, flattery to cover up the Ming Dynasty, and the intolerable harm of evil songs to the public led him to write Li Sao. Li Sao is a magnificent political lyric poem, which has a lofty position in the history of China literature. Written when Qu Yuan was exiled to the south of the Yangtze River, it is a poet's work full of patriotic passion.