Flash: Understanding Program Flow?

Specifically, I have a demo of a flash game (sort of super mario style). In it I have two types of weapon - a simple fire and big fireball. I reviewed the code in order to learn flash better [I am very new - since around monday this week].

I saw that the program has a variable that keeps track of the number of uses I have left in each weapon. I tried to review all the places this variable was used but I couldn't find where it affects the drawing onto the screen.

I even tried removing the variable declaration and then testing it - so I may find all references to the variable -- By the way any convinient way of finding all references to a variable/method/class [I am using ADOBE FLASH CS5.5]?
Also, I tried changing the variables starting value to "12" and I noticed that when I test the game, the weapon has 12 uses indeed.

So my problem:1. It seems that this variable is somehow affecting the drawing. Yet, I don't know how it does so since all the code I have found that uses this variable has nothing to do with drawing. It is all, logic, like

if(var <= 0){
var--;
} else{
return false;
}

Where is this influence coming from?get all references to a variable[like in eclipse ctrl+shift+g]?