READ_TEXT FM Issue (Passing Table "Lines")

I am trying to print out additional text that is entered in the "item text" section when creating the sales order. I am trying to call the READ_TEXT FM to read out the additional text, but I get the following error when I try to print preview it in vf02.

The reason for the exception is:

When calling the function module "READ_TEXT", one of the parameters needed according to the interface description was not specified.

This parameter was "LINES".

I know I don't pass the table "LINES" simply because 1) I don't know what table that is 2) I don't know what type of table it is and the data it contains.

DATA:
      temp_id TYPE thead-tdid,
      temp_language TYPE thead-tdspras,
      temp_name TYPE thead-tdname,
      temp_object TYPE thead-tdobject.

temp_id = '0001'.
temp_language = 'EN'.
temp_name = '0090000068000050'.
*temp_name = gs_it_gen-bil_number + gs_it_gen-itm_number.
temp_object = 'VBBP'.

CALL FUNCTION 'READ_TEXT'
  EXPORTING
    ID = temp_id
    LANGUAGE = temp_language
    NAME = temp_name
    OBJECT = temp_object
  IMPORTING
    HEADER = extra_text.