A computer-implemented method for optimizing a search index of a search service may be provided. The method may comprise storing continuously search queries of the search service, receiving a content item to be indexed, adding the content item temporarily to the a main index of the search service, determining a set of document relevancy factor (DRF) values for the content item for a selected set of stored search queries, determining a combined document relevancy factor value out of the determined set of document relevancy factor values for the content item, comparing the combined document relevancy factor value for the content item to a document relevancy factor threshold value, and adding, in response to the comparing, the content item permanently to an index based on the results of the comparing.