Data Validation=> List=> code for quickly finding data

Hi and thanks alot in advance for your help

Is it possible to write a code that in data validation=> list, it would become more handy for user to find data more quickly in lengthy lists? For example if s/he writes the first letter of the name , the list goes to that letter (like the drop-down lists we see in internet). Can we set the focus of the list to a default data?