The bold part.
For all the rest of his life he had a special warm feeling for kitchens and those peculiar sounds and smells that seemed somehow to combine into a bustling seriousness that had to do with love and food and comfort and security and, above all, home.
I don't understand about if it is a reference to 'a special warm feeling' or 'sounds and smells'?
For all the rest of his life he had a special warm feeling for kitchens and those peculiar sounds and smells that (these feelings or these sounds and smells?) seemed somehow to combine into a bustling seriousness that had to do with love and food and comfort and security and, above all, home.
The same with 'that had to do with love...'