Titles shown in Vietnamese (5)
I believe the answer is:
names
'titles' is the definition.
(I've seen this in another clue)
'in vietnamese' is the wordplay.
'in' says the answer is hidden in the clue.
'NAMES' is hidden within 'vietnamese'.
'shown' acts as a link.
(Other definitions for names that I've seen before include "celebrities" , "identification" , "Some people drop these to sound important" , "Appellations or identifiers" , "Titles" .)