1. One or more computer-readable media storing computer-executable instructions that, when executed by one or more processors, performs acts comprising: receiving product information associated with a product; conducting word segmentation on the product information to generate a phrase that includes one or more word segments; finding relevancies between the phrase and product categories corresponding to multiple nodes having one parent node in a product category tree, each of the multiple nodes corresponding to one product category; and selecting a node from the multiple nodes based on the relevancies.