1. A system for search with more like this refinements, comprising: a processor configured to: receive a product and a context; determine a product class, comprising to: weigh a first product by a first weight to obtain a first weighted product, the first weight relating to a strength of association of the first product to the product class; weigh a second product by a second weight to obtain a second weighted product, the second weight relating to a strength of association of the second product to the product class; and determine the product class based at least in part on the first and second weighted products and a function; generate a search query based on the product, the product class, and the context; determine a field boost associated with the search query, comprising to: determine a first match of a first string of the search query with a first field of a merchant's web page including the product; determine a second match of a second string of the search query with a second field of the merchant's web page including the product, the first field being different from the second field; weigh the first field with a third weight to obtain a first weighted field; weigh the second field with a fourth weight to obtain a second weighted field, the third weight being different from the fourth weight; and obtain the field boost based at least in part on the first and second weighted fields; and determine a plurality of products that match the search query to generate more like this search results, wherein the plurality of products that match the search query is determined based at least in part on the field boost; and a memory coupled to the processor and configured to provide the processor with instructions.