The Global Search option in Zoho CRM is nice if you are not exactly sure where something is stored in your database. Most commonly, Zoho CRM users will use the Global Search option, because it is so predominantly displayed at the top right of the screen. This option allows you to search through all modules for the information that you want to find. You can even use the drop-down to limit the search to specific modules.
However, if you know what you are looking for, it is not necessarily the fastest way to find it.