I think your xml file should be structured with description, weight, class, rate and charges as children of the typeCharge, like:
Code:
<typeCharge name="FS">
  <description>LTL FUEL SURCHARGE OF 28.50&#37;</description>
  <weight />
  <class />
  <rate />
  <charges>45.67</charges>
</typeCharge>
Then you loop through the typCharge items and check to see if its the one you want. Once you have it you get its children and find the charges one.

Or, you could have it like below and replace ITEM with something else:
Code:
<ITEM>
  <typeCharge>FS</typeCharge>
  <description>LTL FUEL SURCHARGE OF 28.50%</description>
  <weight />
  <class />
  <rate />
  <charges>45.67</charges>
</ITEM>
Both these ways the items are grouped in a way that they relate to each other.