Text entry must contain

Hi Jerry, Not sure if you can help again.  I am trying to get the java scrip to include upper case and lower case, so I have just copied and pasted the line relating to the word and changed the first letter to upper case.  This now only accepts the upper case word and ignores the lower case.  Are you able to help?

var player = GetPlayer();

var str = player.GetVar("draincoolant");
var n = str.search("drain");
var n = str.search("Drain");
var m = str.search("coolant");
var m = str.search("Coolant");

if(n >= 0){
player.SetVar("draincoolant", "Drain coolant"); 
}else if(m >= 0){
player.SetVar("draincoolant", "Drain coolant"); 
}else{
player.SetVar("draincoolant", str);
}