Yeah, 
str len (String) 
-> sets #Strres to the Length of the String
str Count (String) (Sub String) 
-> sets #Strres to the # of Sub Strings in the String ; so if you Did a count of the # of "resist" in The property of  Most armor, it would return 5 
Str Pos (String) (Sub String) (Index)
-> Sets #Strres to the Numeric Location of the Indexed Sub String. 
Str Pos _This_ _ 2 ; Would Find the Location of the Second _ in the String "_This_ "
Str Pos is Usually used in Conjunction with  Str Count to determine how many instances or to Increment the Index's
Str Left (String) (Length)
-> Sets #Strres to the Part of the String from 1 to "Length" 
Str Left This 2 
-> #Strres = Th
Str Right (String) (Length) 
-> Sets #Strres to the part of the String from the End in (Length) distance 
Str Right This 2 
-> #Strres = is
Str Mid (String) (Start) (Length)
-> Sets #Strres to the Part of the string from the Start to Start + Length 
Str Right and Str Left become obsolete as you learn to use Str Mid
Str Lower (String)
-> Turns Penguins into llamas. Or Something like that... Honestly Never Used it. I'd Imagine it Forces everything to Lower Case
Str Ins (String) (Sub String) (Start) 
-> Inception of a string inside a string..... 
Str Del (String) (Start) (Length)
-> Sets #Strres to the Leftover String after you Chop it into Pieces
Those are all the Commands Described in a fairly basic way.... 
Some Handy Pointers when it comes to handling Property Strings. 
#Property isn't the same as Journal. You don't have _ instead of Spaces. Instead you have actual Spaces. So Physical Resist becomes Physical , #Spc , Resist in EUO. 
Learn to Use Str Count, Str Pos, Str Mid and you can Pull just about any Data you want out of a string.