I'm not aware of a direct way. And generally speaking, I would prefer to train users in how QlikView works, not modify QlikView to behave the way the users expect, because then I'm adding extra maintenance work (and extra possibility of bugs) for that application and every future application, at least if I want to keep my interface consistent. All the user has to do in this case is manually delete the asterisks. It's an annoying extra step, yes, but probably MOST of the time when people are using a search box, they're not looking for a specific value, they're searching for values matching a pattern.
That said, YES, I think you can do what you want in an indirect way. Consider using an input box instead of a search box. Create a variable and an input box for that variable. Trigger an action OnInput of that variable that does a select in your account field of the value in the variable. They could probably type in asterisks manually for something more like the normal search box, but they wouldn't appear by default, so the default behavior would be to select the exact account number they typed. That sounds to me like what you're looking for?
