Problem:
The user would like to have a search, with term fields, in a taxonomy view.

Solution:
Custom search is not possible for taxonomy views and user views. It is only possible for post views. We have an existing feature request for custom taxonomy searches and I have added your voice to the request.

You may also confirm it in our feature request form https://toolset.com/home/contact-us/suggest-a-new-feature-for-toolset/

However, I believe that a workaround can be implemented using custom code. At the end, taxonomy views are just a wrapper around a WP_Term_Query instance. And we do offer a hook to modify the arguments that would be passed to it:

Relevant Documentation:

• https://toolset.com/documentation/programmer-reference/views-filters/#wpv_filter_taxonomy_query
• <https://developer.wordpress.org/reference/functions/get_terms/
• https://developer.wordpress.org/reference/classes/wp_term_query/