1. A method comprising: obtaining a designated query intent from a search query; in response to obtaining the designated query intent from the search query, obtaining a second wiki article corresponding to the designated query intent, wherein the second wiki article includes a second title, a second body, and a plurality of respective links; obtaining a plurality of first wiki articles that correspond to the plurality of respective links included in the second wiki article, wherein each of the first wiki articles includes a different title and a different body; extracting a plurality of first titles of the plurality of first wiki articles; extracting the second title of the second wiki article; generating an initial key term set including the plurality of first titles and the second title; correlating each of the plurality of first titles and the second title with at least one respective clicked uniform resource identifier based on a search click log, wherein the search click log comprises a record of historical search queries provided by users and documents clicked by the users from search results retrieved in response to the historical search queries, and wherein each of the documents has a respective uniform resource identifier; generating an expanded key term set to include the initial key term set expanded to further include search terms correlated to the at least one respective clicked uniform resource identifier; training a search query intent classifier to classify search queries with respect to the designated query intent based on the expanded key term set; obtaining the designated query intent from a subsequent search query; and in response to obtaining the subsequent search query corresponding to the designated query intent, controlling the trained search query intent classifier to select advertisement data based on the expanded key term set.