1. A method performed by data processing apparatus, the method comprising: receiving one or more characters from a user device; obtaining an auto-completion corresponding to the one or more characters; obtaining data identifying multiple corpora and a respective corpus score associated with the auto-completion for each identified corpus; selecting a first corpus of the multiple corpora whose corpus score satisfies a threshold and a universal search corpus that includes two or more of the multiple corpora and excludes the first corpus; and providing, for display in a drop-down menu and to the user device, a first drop down entry that indicates a first instance of the auto-completion and that includes an icon representing the first corpus adjacent to the first instance of the auto-completion, and a second drop down entry that indicates a second instance of the auto-completion that corresponds to the universal search corpus and that excludes the icon representing the first corpus, wherein the universal search corpus includes two or more of a web search corpus, a places search corpus, a literature search corpus, a patent search corpus, an images search corpus, a videos search corpus, a news search corpus, a shopping search corpus, and a blocs search corpus.