Mikko Saari on "[Plugin: Relevanssi - A Better Search] how to create and search multiple taxonomy lists"

Hi,
I'm building a medicinal plants site, I'm using the Advanced Custom Fields plugin and have many taxonomy fields - some multi select. What I would like to do is create a dropdown select list for each taxonomy, select the term that I'm looking for from each taxonomy, and then submit a Search, which would result in a list of all the plants that contain all the taxonomy terms.
Here's an example of what I want to do.
If this can be done using Relevanssi, please can you give me some pointers to the best way to do this - my PHP skills are not too strong.
Thanks for any help
David

https://wordpress.org/plugins/relevanssi/

Multi-taxonomy searches can be done with Relevanssi and in theory it's quite simple: just read in the taxonomy parameters and create a well-formed tax_query out of it.

Here's some instructions with sample code: http://www.relevanssi.com/knowledge-base/multiple-custom-taxonomies/