Search engine process operates on data collections to expand a user's knowledge about select content (SC) words, data objects, etc. A prioritized hierarchical taxonomic system (H-tax-sys) encompasses some SC is set, input data is classified thereto, and non-matching data (non-SC) is identified. The non-SC are used as a search terms. Additionally-optionally, the process identifies input data as SC per n priority H-tax, and uses these as search terms. Additionally-optionally, input data matching SC is added as search terms. Additionally-optionally, search terms are extracted from the input based upon H-tax. Supplemental documents are gathered, H-tax classified, mapped and represented with and without mapped search terms.