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I'm looking for the cheapest round-trip ticket from Ho Chi Minh ( Vietnam ) to Los Angeles. The minimum price is around 670 USD. On the contrary, If I book the ticket from Los Angeles to Ho Chi Minh (Vietnam), it only costs 493 USD.
I used Skyscanner / Momodo / Google flight, etc. to try to get the better deal, but those do not work.
Do you know why the flight from US cities to Vietnam is cheaper than from Vietnam to a US city?