You can add this column in your filters. While in the helpdesk, look to the top left and you will see a select columns button. Click it. Look in the available ticket fields box. You should see a field named created. Click it then click the blue arrow that point to the right. The field will be added. Now you can use the up and down blue arrows at the bottom of the show fields box to set what order you want the fields to appear in. Click on the created field, then click the blue up arrow until it is in the place you want it. Click ok. If you want to save the view click the save button (disk icon)