Removing Characters From A String

is there a way to do this in VBA in Access I looked at trim but it does not help much

Dim MyString, TrimString
MyString = " <-Trim-> " ' Initialize string.
TrimString = LTrim(MyString) ' TrimString = "<-Trim-> ".
TrimString = RTrim(MyString) ' TrimString = " <-Trim->".
TrimString = LTrim(RTrim(MyString)) ' TrimString = "<-Trim->".
' Using the Trim function alone achieves the same result.
TrimString = Trim(MyString) ' TrimString = "<-Trim->".

I have a select statment setting the data that will be in a combo box
I would like to trim this data...

for example the select statment returns something like
category>subcatgory>field>subfield

so I want to trim it down to be
field>subfield