Scoring of complex queries involves a few different pieces. To understand how they fit together, it's helpful to first look a simple query, then add in complexities one at a time until we have the complete picture.
The simplest query we can run is a term query for a single term. Consider a term search for light in the field description of the beer-search dataset. The top scoring hit is iron_city_brewing_co-ic_light and when we ask Bleve to explain the scoring we get:
"explanation": {
"value": 2.024174152548743,