Answer: Self-sacrifice and loyalty
Step-by-step explanation:
Ha wants Khoi to be happy and not to be so sad at that moment so she wants to ease her pain by offering up her doll. After that, they both, Khoi and Ha, are tossing them into the sea together and she misses her doll right away but deep down she knows that it was the right thing to do.
That is why the doll is showing self-sacrifice and Ha's love for her family and also loyalty to them.