Вы можете использовать
Mid(string,start[,length])
string - Required. The string expression from which characters are returned
start - Required. Specifies the starting position. If set to greater than the number of characters in string, it returns an empty string ("")
length - Optional. The number of characters to return
или используйте
Split(expression[,delimiter[,count[,compare]]])
expression - Required. A string expression that contains substrings and delimiters
delimiter - Optional. A string character used to identify substring limits. Default is the space character
count - Optional. The number of substrings to be returned. -1 indicates that all substrings are returned
compare - Optional. Specifies the string comparison to use.
Can have one of the following values:
* 0 = vbBinaryCompare - Perform a binary comparison
* 1 = vbTextCompare - Perform a textual comparison