Assuming that you have bound the files to the chema correctly, then you will have to import that data file when theform is opened on the client. You can do tyhis through menu options in Acrobat or you can have a button that will allow the user to choose a data file to import. AS long as the data file follows the same structure of the one that was defined in the template then your data will appear.
Two other options exist - use a server side product to merge the data onto the template before the PDF is rendered. Or, have a reference to the template that is being used in the xml file (change its extension to xdp) and double click the xdp file. This will casue the template to open and the dat file to be merged into the opened file. This assumes that you have the template on yor local machine and that you DO NOT have Designer on that machine (XDP extensions are associated with Designer as well as Acrobat).