1. A method comprising: selecting, by a computing system, a knowledge element from a knowledge corpus of an enterprise for extraction of n-grams; deriving, by a computing system, a term vector comprising terms in the knowledge element; identifying, by the computing system, key terms in the term vector based at least on a frequency of occurrence of each term in the knowledge element; extracting, by the computing system, n-grams using the identified key terms; scoring, by the computing system, each of the extracted n-grams as a function of at least a frequency of occurrence of each of the n-grams across the knowledge corpus of the enterprise; and adding, by the computing system, one or more of the extracted n-grams to an index based on the scoring.