The Search Builder function and Search History replace the former Preview/Index page. The pull-down list shows all indexed fields for the database. The Show Index link (green arrow) expands the display to show all terms indexed for a particular field. The bottom panel shows the index for the Protein Name field matching the search term creatine kinase. Entries from the Search Builder and the Search History can be combined in the Search Box to construct complex queries. Clicking on the numbered entries in the Search History provides Options for combining searches, removing History entries, loading results, showing queries, and saving the search in My NCBI. Combining #2, #5 and #3 finds the two Xenopus RefSeq proteins for prolactin.