Can I apply a hardships waiver if I have 2 young children cannot speak Vietnamese. I'm j1 visa with 2 years residents requirement

You could apply for a J-1 waiver based upon exceptional hardship to your children, but it is not clear whether you have sufficient hardship. Simply having young children who are unable to speak Vietnamese may not be sufficient. More information is needed about your children to assess whether you can establish exceptional hardship. You can read more about hardship factors at http://myattorneyusa.com/extreme-hardship.