2008 visual studio combo box show only what you have entered in drop down

what i want is only to have what you entered be the only things that show
as you type in your choices get less and less
i am putting them in a array so I do not have to call the database each time
i want the cursor to stay in the entry box where it can enter the 2nd  3rd choice

i know about   ComboBox1.DroppedDown = True to show drop down after
you enter

ie data

3311
3312
3423

enter 3
get
3311
3312
3423
enter 33
only get
3311
3312

with out the cursor going back