issue with data entered as a range with wild card char

Hello,

I have an internal table it_data with all vendor data in it. I also have a selection screen with fields like name, number and address. A user can enter anything on the selection screen and based on thatI need to show the results. I am having issues with when user enters a city as a range with wild card charachter. So let's say user entered A* to D*, so it should show all the cities between A* and D*, for this I have written the below code:

           wa_ort01-sign   = 'I'.
           wa_ort01-option = 'BT'.

           wa_ort01-low = s_ort01-low.

           wa_ort01-high = s_ort01-high.

   IF r_ort01 IS NOT INITIAL.
      LOOP AT it_data ASSIGNING <fs_data>.
        TRANSLATE <fs_data>-ort01 TO UPPER CASE.
        READ TABLE r_ort01 INDEX sy-index into wa_ort01.
        IF ( <fs_data>-ort01 CP wa_ort01-low ) or ( <fs_data>-ort01 CP wa_ort01-high ).

        ELSE.
          DELETE it_data.
        ENDIF.
      ENDLOOP.
    ENDIF.

when I run my code I only see the vendors with cities starting with A* and D* and nothing in between like cities that start with B or C. I know the problem is that I am checking the pattern for the low and high value of the value entered by the user and hence ignoring anything between but I am npt sure how to fix it.

Any suggestion.

Thank you.