Search for file "th-product-review.liquid" in Admin code. when you open this file you will see CSS & JS file, Whenever you update CSS or JS file at that moment you need to pass a random number as a parameter as shown in after changes image.

For example:
{{ '//' | stylesheet_tag }}

{{ '//' | script_tag }}

Default Code before changes:

Code after changes:

Note: Whenever single change made in these CSS or JS file then must change the value of passed parameter.