Tags are stored in the database so they will not be transferred when importing a hand history sample into a different database. To transfer tags would require the creation of a database backup on the laptop which can then be restored on the desktop:
Guide: Backup & RestoreAnother option if the amount of tags in each of your imports is manageable each time then you could export the tagged hands only first. Go to 'My Reports' and create a hand report:
Guide: Creating My ReportsFilter for the tags you want, select all the hands in the report and then export them via the right click menu. You can then import those hands onto the desktop and retag them before importing the remainder of your hands.