gd morning.
This "la lun sio" is hardly use in Sg but common in older Indon
Hokkiens. In Sg "pua sio leng" is more often used.
"la lun sio" actually means not too hot.
Singaporeans also use " la lun sio " actually. If not, how
come I know leh? 
Just that I am surprised someone from the coffeeshop industry
who is a Hokkien herself and usually speaks Hokkien most of the
time, dunno " la lun sio ". Not as if I am asking an
Engineer, a Construction worker, a Banker, a Pilot or whatever,
I was surprised because she handles so many coffeeshop
patrons in every day and still never heard about " la lun sio "
? 
