How to split multiple ComboBox entries into multiple lines in Sharepoint using PowerApps?

Question

Below is a code I found on https://www.powerplatformguide.com/post/patching-combo-box-inputs-power-apps

This code splits Combobox2 multiple entries into multiple lines. How do I alter this code for multiple Combobox accepting multiple entries each? I would like different line items to be saved for each combination.

ForAll(
      Split(
            Concat(ComboBox2.SelectedItems,Value,", "),", "),
            Collect(boxCol,Result);
            
Patch(DS, Defaults(DS),
  {
      Name: Input_Name.Text,
      Age: Value(Input_Age.Text),
      'Date of Birth': Input_DOB.SelectedDate,
      'Favourite Car Brand': Dropdown_FavouriteCarBrand.Selected.Value,
      'Favourite Car Colour': Result
  })
);

Answer 1

What do you mean with each combination?

An item has 2 Comboboxes. Let's say, combobox 1 has the values A, B and C, and combobox 2 contains 1, 2, 3, and 4. A user selects A and C from 1 and 2 and 3 from 2, you want the rows: A2, A3, C2, C3?

If so,

ForAll( 
   ComboBox1.SelectedItems // this section will have A... B...
   ForAll(
      ComboBox2.SelectedItems // This Will Give A1, A2.... till the next iteration.
   )
)