no matter what (a) race or (a) creed.

[nemo eve walle]

N-COUNT A creed is a religion.
The centre is open to all, no matter what race or creed.
Example found in Collins dictionary.

Apparently ''creed'' and ''race'' are countable noun, even in the definition, ''creed'' has an article.
''What is a race?'', ''what is a creed?'', even in these questions, the article is needed.
But the example in Collins, there are no articles before ''race'' and ''creed''. Why?

 

[Elwintee]

This is normal in the context. I think the article is omitted because 'no matter what race or creed [visitors belong to]' is understood.

 

[entangledbank]

Wrong questions. 'What' is also used as a modifier of nouns, without an article, so the related direct question is 'What race are they?' (like 'what colour?', 'what size?'). Indirectly: 'I want to know what race/colour/size she is.' It is used with an article in exclamations: 'What a fool I have been!'; and the indirect equivalent: 'She told me what a fool I was'.

 

[Thomas1]

Sorry, but you can ask 'What is a creed?', 'What is a race?', 'What is creed?', 'What is race?' when someone doesn't really know what ther are.