I'm not sure if this can be done or not but any help would be much appreciated.
We have an annual catalogue of all our books each have a unique isbn. Our catalogue is grouped into sections by course books, exam materials etc. each book can have many levels thus giving them many isbn under one level. I can export all of our titles with isbns prices etc into a spread sheet and save as a csv file ready for the data merge into InDesign. However what I am trying to achieve is like the image attached. where all the isbns will be for 1 record at different levels and are able to be displayed as one record before the next record gets produced. As far as I can see I started off with the spread sheet of columns for each level however realised this would then become a problem when we can have over 10 different titles with multiple isbns under the same level. Hopefully my images will explain a little bit clearer!