1. A computer-implemented method comprising: receiving user input identifying tabular source data, the tabular source data representing data that has a tabular structure; receiving user input specifying parameters for a search of a plurality of documents, the search intended to find information resembling a data portion from at least one random row within the tabular source data, the search parameters identifying at least one characteristic of the data portion without revealing the content of the data portion; defining, based on the search parameters, a scope of the search to find, in any of the plurality of documents, a sub-set of data fragments that resembles the data portion from at least one random row within the tabular source data; and searching each of the plurality of documents for the information resembling the data portion from at least one random row within the tabular data source using the defined scope, wherein the search is defined to find, in any of the plurality of documents, a sub-set of data fragments that matches the information from any single row within the tabular source data and includes data from at least a minimum number of columns within the tabular structure of the tabular source data.