I fully understand your point, and I wish this was easier to me as well. I can try explaining how it's done,
1. To create such complex forms, first of all you will have to create and use custom fields. If you are not familiar with them, you can read more in the wordpress codex.
In very short: Custom fields are basically data fields attached to a post or page or a custom post type (like a product, or forum topic). Each and every custom field has a name and a value. The article I linked above will explain how you can create such custom fields.
2. Once you understand how custom fields work, and you maybe created a few for testing, then you can proceed to create the search fields as seen on the TV demo. There is a chapter in the documentation you should read through, which explains fully how you can create these fields: https://wpdreams.gitbooks.io/ajax-search-pro-documentation/content/frontend_search_settings/custom_field_selectors.html
The basic concept of this is, that you can create various items (radio buttons, checkboxes, sliding bars) for any selected custom field.
Let's take the TV size slider as an example:
– First I created all the TV products I wanted.
– Then I opened the first one an added a custom field called “tv_screen_size” and as the value I entered 50. Screenshot.
– I repeated this process for each and every TV product I created. The screen sizes were different for some of them of course.
– Then when I was done entering the fields, I created the range slider on the search options page as following: https://i.imgur.com/w6VS65I.png
– Hit the blue SAVE button on the editor, then the Save All tabs button.
– The range slider should be now visible on the front end.
To add more and more different selectors, just repeat this process.
I'm sorry if something is not clear, it's very hard to explain as the developer as I might see this differently from a customer.
Let me know if you need any more help.Best,
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