1. A computer-implemented method for identifying data files that have a common characteristic, the method comprising: receiving a plurality of data files including one or more data files having the common characteristic; generating a list of key terms from the plurality of data files; classifying each data file of the plurality of data files within a hierarchical structure, the hierarchical structure including upper nodes and lower nodes configured to group data files having similar characteristics, wherein a data file is classified within a lower node of the hierarchical structure based on a psychological characteristic of the classified data file, wherein the psychological characteristic indicates a psychological state of the creator of the classified data file; identifying data files from the plurality of data files having an association with a social community, the social community being a homogenous sub-group of a larger population defined by one or more features, wherein the identified data files having the association with the social community are classified within a particular node of the hierarchical structure that is defined by the one or more features; updating the list of key terms based on an analysis of the identified data files; and using the updated list of key terms to identify other data files that have the common characteristic.