AutoFill combo box

Question

Hi,

i have a combo box with items

Top Flat Bottom Cone
Top Flat Bottom  Tori-Dish
J Top Flat Bottom Cone
J Top Flat Bottom  Tori-Dish
L Top Flat Bottom Cone
L Top Flat Bottom  Tori-Dish

i would like to have a auto fill option for item when i type in letter like "t" or "J" or "L" and followed by subsequent letters to fill the combo box with it items

Thanks for looking to my problem