Maybe Vietnam finally came to mind (4)
I believe the answer is:
ware
'maybe vietnam' is the definition.
I can't tell whether this definition defines the answer.
'finally came to mind' is the wordplay.
'finally' indicates one should take the final letters.
'to' says to put letters next to each other (I've seen this in other clues).
'mind' becomes 'war' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The last letter of 'came' is 'e'.
'e' put after 'war' is 'WARE'.
Can you help me to learn more?
(Other definitions for ware that I've seen before include "Herts town" , "Goods for sale" , "Articles of a specified type, such as pottery" , "Soft..., silver..." , "possible purchases" .)