Hello. You have not informed which book reviews this question is referring to. This makes it impossible for me to answer you specifically. However, I will try to help you as much as I can, giving instructions on how to answer this.
You should read both reviews and observe the position of the review author in relation to the book. It is likely that each author makes different positions on the construction of the narratives, the characters, the writing style, the events, the themes and other elements of the work. These positions can be positive, when they praise the work, or, negative, when they criticize the work. You must identify which author is being positive and which is being negative.