Once a search query is received from a user, a standard index is searched
based on the search query. The standard index forms part of a set of
replicated standard indexes having multiple instances of the standard
index. A signal is then determined based on the search of the standard
index. When the received signal meets predefined criteria, an extended
index is searched. The extended index forms part of a set of extended
indexes having at least one instance of the extended index. There are
fewer instances of the extended index than instances of the standard
index. Extended search results are then obtained from the extended index
and at least a portion of the extended search results is transmitted
towards a user.