Code change does not take place in UI

I am new in erpnext as well as frappe. With my little knowledge of erpnext (expert in python and odoo) am going to work in an existing project.

There is a custom app, and i made some changes couple of files like something.html and something.js. I know this file is rendering in my url but i do not found my expected changes here in UI.

I also close termnial and run bench start. What should i do here?

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