I prefer reading those poems written by Shu Ting.

This leads to an attributive clause in which the antecedent is poetry. Those are only demonstrative pronouns, used as "those" The front is a simple sentence, and I prefer reading poetry. (I prefer reading those poems), so which poems do you mean? If you don't give the poem a limited scope, it will be difficult for the listener to understand what poem you are referring to, so you should give the word poem a limited scope, that is, it was written by Shu Ting. Oh, so what you said was a poem written by Shu Ting, not a Tang poem and a Song poem.