rơ le tần số thấp 
low frequency relay [ rơ ] : to clean
[ le ] : to loll (its tongue)
[ số ] : (1) amount, number, figure, quantity, size (of clothing), digit, edition; digital; (2) gear (of a car); (3) destiny, fate, lot
[ thấp ] : short (of height), low, poor
Most Common Compounds Set 1:
Most Common Compounds Set 2 :