1. A non-transitory computer readable medium storing a program causing a computer to function as: a learning data acquiring unit that acquires learning data; a memory unit that performs machine learning using the learning data about cluster division where Markov chains of transition via a link from a node to a node on a network formed from a plurality of nodes and a plurality of links connecting the plurality of nodes to each other are divided into a plurality of clusters each of which is indicated by a biased Markov chain, and calculates a steady state of each biased Markov chain indicating each cluster of the learning result so as to obtain and store attribution degree information indicating an attribution degree of each node on the network to each cluster of the learning result; a search condition receiving unit that receives a search condition from a user; a cluster extracting unit that extracts clusters suitable for the search condition on the basis of a node group matching with the search condition received from the user and the attribution degree information; a partial network cutting unit that cuts a partial network formed by a node group belonging to the clusters extracted by the cluster extracting unit from the network; and an importance calculating unit that calculates importance of each node on the partial network by executing an operation of a personalized PageRank algorithm having the node group matching with the search condition as a seed vector for the cut partial network, and generates a search result to the user regarding the search condition on the basis of the calculated importance.