I have been researching the search capabilities of shopify. Although there is no official word on it, it sounds like it's based on Apache Solr engine. I went through the page at https://help.shopify.com/manual/sell-online/online-store/storefront-search
However when I wanted to use more advanced features of Solr to boost order of certain fields in the results, they all seemed to be ignored. Is there a way to execute more advanced Solr queries whether by using dismax or lucene query types etc?
Short answer is 'no'. There may be Apps that offer that functionality though so check out the App store.