Netsuite names are typically unique within your Netsuite instance - i.e. you cannot have customers with the same name, items of the same name or invoices with the same number. As such, when you pass in your search criteria into the Netsuite search actions, you will usually only get one record back if the criteria matches that of a record in Netsuite, or get nothing back if your criteria does not match any record in Netsuite.