"Reflection on reading" or simply "Reading reflection" is a more commonly used term in Engpsh for "读后感". "The" is not typically added before "reading reflection".
Here are some examples:
"I wrote a reading reflection on the novel I just finished."
"The teacher asked us to submit a reading reflection on the article we read in class."
Note: "Reading reflection" is a term used in academic or educational contexts to describe the process of thinking about and analyzing a piece of text after reading it.