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Hello there,
I’m preparing a page for vendors in Dokan. Here I am preparing a page for the categories. There will be categories on the page. After clicking these categories, the commission amount etc. containing files will be downloaded.

Coming to my question, I am writing the page in HTML. I want it to be possible to search in categories. However, the code below can only search for the Main Category. For example, A. But I want to search in subcategories as well. For example, D2 cannot be found in the search result. I wonder where does the problem arise?

https://i.ibb.co/8s68cjW/bcs.png