I don’t even know what you mean by talking about “trust” in their vote.
I know that they vote more conservative than other Asians and Orientals.
As NBC and other sources say “For example, Vietnamese Americans historically lean more Republican, while Indian Americans tend to vote more for Democrats.”
Here is a quote from an NPR article and the numbers they give for 2016 are from the hard-left Asian American Legal Defense and Education Fund, or AALDEF https://aapifund.org/wp-content/uploads/2019/05/2016-Eve-Poll-Item-Slideshow-Results.pdf
“Trump also saw a drop in support from Vietnamese-American voters, historically a base of Republican support among the Asian-American electorate. While 54 percent supported Romney and 67 percent supported McCain, Trump only won 32 percent of the Vietnamese-American vote.”
Misled and misinformed: Why Vietnamese voters make up the largest Asian demographic in favor of Trump
https://stanforddaily.com/2020/11/10/misled-and-misinformed-why-vietnamese-voters-make-up-the-largest-asian-demographic-in-favor-of-trump/
Why are Vietnamese the most Republican-leaning Asian Americans?
https://www.washingtonpost.com/nation/2023/07/03/vietnamese-republican-democrat-politics-vote/
Why did Vietnamese voters in Orange County swing toward Trump in 2020?
https://www.ocregister.com/2021/03/07/why-did-vietnamese-voters-in-orange-county-swing-toward-trump-in-2020/
US election: Vietnamese-Americans prefer Trump to Biden — and the president has fans in Vietnam too
https://www.scmp.com/week-asia/politics/article/3104015/us-election-vietnamese-americans-prefer-trump-biden-and
Support for Trump is tearing apart Vietnamese American families-48 percent of polled Vietnamese American voters say they prefer Trump to Biden.
https://www.vox.com/first-person/2020/10/30/21540263/vietnamese-american-support-trump-2020
Vietnamese-Americans more likely to vote for Trump, survey says. How are their liberal kids coping?
Out of all the Asian groups surveyed, Vietnamese was the only one that still swung right, reminding young liberal Viet voters of their disconnect from their parents’ views.
https://www.uscannenbergmedia.com/2020/09/21/vietnamese-americans-more-likely-to-vote-for-trump-survey-says-how-are-their-liberal-kids-coping/