It is not clear what you mean by "small like fish." Can you please clarify your question?
For example:
* Are you asking about a physical comparison? Are you wondering about the size of something in relation to a fish?
* Are you asking about a metaphor? Do you want to know what it means to be described as "small like fish" figuratively?
* Are you asking about a specific phrase? Do you have a particular saying or idiom in mind?
Once you provide more context, I can help you understand what it means. 😊