A really good hardback can help (3)

I believe the answer is:

aid

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'help' is the definition.
(synonyms)

'a really good hardback' is the wordplay.
'really good hardback' becomes 'id' (I can't explain this - if you can you should believe this answer much more).
'a'+'id'='AID'

'can' acts as a link.

Can you help me to learn more?

(Other definitions for aid that I've seen before include "Help or succour" , "Help or support" , "A hand" , "Relief" , "grant" .)

I've seen this clue in the Evening Standard.

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