Extract Substring from String

For the life of me I cannot find a function that extracts a substring from an existing string.  The closest I could find was SearchSplit String and Replace Substring, but neither of them do what I want.

This is what I want to do:

Assuming a string "Test String", the letters are in positions as follows:

T e s t _ S t r i n g
0 1 2 3 4 5 6 7 8 9 10

Now extact substring from offset 5 to position 7 (Length 3):

Substring = S t r

            5 6 7

In Java, for example, you can easily do this using the code below:

String str = "Test String";

String subString = str.substring(5,7);

Is there no simple function to do this in LabVIEW?  If not, what's the easiest way to do this?