How do I create dynamic dropdowns that works 2 ways?

I have an Order Form sheet set up with a fair bit of code in the background. Part of the Form has order lines with headers of Code, Category and Product Description. I have a separate Products list which I wanted to create the dynamic drop down lists using formulas.

I soon found out that you cannot type a FILTER formula directly into the Excel Data Validation source box. After a bit of researching, I figured how to to create dynamic dropdowns by referencing a spill range.

The way I've set it up is probably a bit messy (but it works). At the moment the user has to select the category of product they want first. Then the drop down list in Product Description will show only items in that category. When they select the item they want, the drop down list for Code will show the specific code that item relates to.

It can work but I was hoping to be able to use partial searches in any of the 3 columns to generate suggestions. eg. Start typing partial item name which would then narrow down options in the drop down list for Products as you type each letter. Select the item and the category and Item Code self populates. Also enable the user to partially type item code or category for a similar result.

Hope this makes sense. And if so, any ideas?