bỏ ngỏ 
to leave open (door or window) [ bỏ ] : (1) to leave, quit, abandon (a policy), drop, divorce; (2) to insert, put, invest (into)
[ ngỏ ] : to be open (door); to reveal, express
Most Common Compounds Set 1:
Most Common Compounds Set 2 :
bỏ ngỏ to leave open (door or window)