Formal expression method and device oriented to text search demand and storage medium

The invention discloses a formal expression method and device oriented to a text search demand and a storage medium. The method comprises the following steps: converting search input texts into word sequences according to certain specifications; through a statistical method, extracting hot words and a first number set from the word sequence, wherein the hot words are words most capable of representing the input texts, and the first number set is a numerical value set representing the importance degree of each word sequence; according to the word sequences and the hot words, searching a corresponding ontology through semantic mapping and feature word matching; classifying the ontology into an upper ontology, a lower ontology and a related ontology; calculating weights of the upper ontology, the lower ontology and the related ontology according to the first number set; and constructing an instance of the search demand formalized expression model. According to the method, development, maintenance and expansion o