Countenance giving away nothing in cafe managed by Rod (5,4)
I believe the answer is:
poker face
'countenance giving away nothing' is the definition.
'poker face' can be an answer for 'countenance' (I have seen 'inscrutable countenance' mean 'poker face' so perhaps 'countenance' could also mean 'poker face'). I am not certain of the 'giving away nothing' bit.
'cafe managed by rod' is the wordplay.
'managed' is an anagram indicator.
'by' means one lot of letters go next to another.
'rod' becomes 'poker' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'cafe' anagrammed gives 'face'.
'face' after 'poker' is 'POKER-FACE'.
'in' is the link.
Can you help me to learn more?
(Other definitions for poker face that I've seen before include "Impassive visage as employed by card gambler" , "Inscrutable expression assumed to conceal emotion" , "Inscrutable person" , "unreadable profile" , "Countenance giving nothing away" .)