What are the possible ways to send money in and out of Indochina countries?

I assume you are referring to countries like Laos, Cambodia, Myanmar, Vietnam when you say ‘Indochina countries’. For these countries, the local banks are less developed and connected to banks in the rest of the world. 

Depending on where you are, the local banks in Indochina may or may not have direct relationship with the beneficiary bank. This will mean that the banks will probably need to go through an intermediary bank, so you can expect the time required for remittance to be delayed. 

If you are transferring large payments out of Indochina, the local banks will need to report to central bank, and you will most likely be asked for the reason for sending the money out. You may be required to fill up some forms, depending on the reason of fund transfer. When sending the money, it is advised that you only transfer money that belongs to you and you are able to give proper explanation to the funds.

You can also use fund transfer service providers like Western Union, Transferwise, Remitly, etc. The transfer fees charged by different service providers may vary, and you have to check with them individually.