A mechanism is provided for retrieving candidate answers from a corpus of documents. The mechanism receives an input question for which an answer is sought. The mechanism extracts features of the input question based on a natural language processing. The mechanism executes a first search of the corpus of documents based on a first subset of the extracted features of the input question and an initial evaluation of a utility of the first subset of extracted features to generate a subset of documents. The mechanism executes a second search of a set of passages extracted from the subset of documents based on a second subset of the extracted features of the input question and a reevaluation of the utility of the second subset of extracted features thereby forming a subset of passages. The mechanism generates query results from the subset of passages matching from which candidate answers are identified.