>It's a software for parking lot that I developed one year ago
>
>Car tags standard here are 3 letters and 4 numbers as: QAX9191
>
>To prevent customers to type QAX919 (motorcicle or foregner tags) and find the car tag QAX9191 accidently
>I turned "set exact on"
>
>However a customer of mine wants to search only by the car tag number
>
>He wants to type 9191 and finds QAX9191
>
>The problem is that I use the whole search in unique textbox
>
>Is it possible to solve this problem withtout adding another textbox or a "set exact off " button ?

One thing you could do would be to run both exact and inexact/partial queries, and present both sets of results.