The index for search module fields is global. This means that you need to have only one value for 0, one value for 1 and so on. When you set the first item of each category to 0 and do the same for fields coming afterwards, you will have multiple zeros, multiple ones and so on and since the system renders them globally, all zeros will be shown under each other, then all ones and so on and this in not how you would like the search fields to appear.

You need to set the index globally so that search module renders as you expect.