1. A method performed by a server system, comprising: receiving a first search query from a user; determining a topic associated with the first search query; determining a second search query as a suggested query to guide the user into interaction with other users who have submitted similar search queries, the second search query being associated with the topic and being different from the first search query; sending the second search query to the user; receiving a selection of the second search query from the user; determining a second query traffic volume, the second query traffic volume indicating a number of times the second search query has been received from other users within a time window; determining that the second query traffic volume is greater than a predetermined threshold traffic volume, the threshold traffic volume being indicative of a level of interest in the topic; and in response to determining that the second query traffic volume is greater than the threshold traffic volume, sending an invitation to the user, the invitation for inviting participation in an online social group comprised of other users who have sent the second query to the server system within the time window.