A system for finding and presenting content items in response to keystrokes entered by a user on an input device having a known layout of overloaded keys selected from a set of key layouts. The system includes (1) a database containing content items and terms characterizing the content items; (2) input logic for receiving keystrokes from the user and building a string corresponding to incremental entries by the user, each item in the string having the set of alphanumeric symbols associated with a corresponding keystroke; (3) mapping logic to map the string to the database to find the most likely content items corresponding to the incremental entries, the mapping logic operating in accordance with a defined error model corresponding to the known layout of overloaded keys; and (4) presentation logic for ordering the most likely content items identified by the mapping logic and for presenting the most likely content items.