16. The computer program product according to claim 15 , wherein the computer readable program code is configured to identify, in each of the second lists, a number of the second search results that are stable.
15. A computer program product, the computer program product comprising: a non-transitory computer readable storage medium having computer readable program code embodied therewith, the computer readable program code comprising: computer readable program code configured to receive a first query term from a user; computer readable program code configured to submit, to a search engine, a first query comprising the first query term; computer readable program code configured to receive, in response to submitting the first query, a first list comprising first search results having respective first rankings; computer readable program code configured to derive multiple keywords from the first query term; computer readable program code configured to submit, for each given derived keyword, a respective second query to the search engine, the respective second query comprising the first query term and the given derived keyword; computer readable program code configured to receive, in response to submitting each of the respective second queries, a respective second list comprising respective second search results having respective second rankings; computer readable program code configured to compute, for each given first search result appearing in one or more of the second lists, a stability score that computes a stability of the given first search result across the second queries by measuring a difference between the first ranking of the given first search result from the first query in the first list and the second rankings of the given first search result in the second lists; computer readable program code configured to re-rank the first search results appearing in one or more of the second list based on their respective first rankings and stability scores in a manner preferring first search results having stability scores indicative that their ranking in the second lists is greater than or equal their ranking in the first list; and computer readable program code configured to present the re-ranked first search results to the user.