Mourn for love (the lyrics are sad and meaningful. This song was sung by an unknown singer Dong Zhen. I suggest you watch a MV while listening to this song. It's called East Palace, which belongs to Liu Shishi and Hugh. Listen to this song and watch the MV.
3. "old boys" (also the song of Chopsticks Brothers, the lyrics are really good! I'm not lying to you! Very amazing! )
4. "My Self" (a Japanese song, but you can read the Chinese meaning, I like it very much, and it is about what one yearns for most).
I think these are very meaningful and highly recommended!