This is for the "search" help text, when in a folder, to more clearly indicate that it will search the server, when it does (it may not, e.g. POP3 accounts).
Shown *inside* the search field, i.e. "input hint".
This is existing:
<string name="search_folder_hint">Search folder</string>
This is NEW:
<string name="search_folder_hint_server">Search folder and server</string>