I use Variant Matrix (https://virtuemart.net/news/468-virtuemart-3-0-6-with-completely-redesigned-multi-variants)
I cannot find, where mulivariant values stored in mysql base
Created a full SQL dump, tried to search by text, but unsuccesful
Help please
virtuemart_product_customfields table - customfield_params field
Don't search text. This is stored once only.
Search related IDs instead. It's somewhat cumbersome because of very strong normalization.
hth, diri