A little help on Conditional bracket

Hello,
I edited the basic search of WordPress (woocommerce), and it works just fine for doing what I want, but as I love and use your search in other sites I bought a license for this site too.

Now, The edit I did to the basic search are several PHP conditional on custom and normal filed of products

This is one example: (there are several and more deep stuff)
Product with
Stock 0 show: Out of Stock (instead of the price)
But a product with the stock at NULL show the price (as are “infinite”)

I try to use your Conditional bracket but it looks quite limited I can’t check a number or a null and do a deeper if concatenation.
Can I eventually put my rule by code and where?

I had another small issue as I used the _price_html but instead show 25.00$ 22.00$ just show the sale price.

Thanks for your time guys, I hope to use this plugin on this site too as I Love it, I just have to figure out how to inject this particular rules