Trump did much better with foreign-born Asians than US-born Asians, especially those with low English proficiency levels. That accounts for the slight swing towards Trump among SOME Asian ethnic groups (mostly Vietnamese-Americans).
Of course, Biden still got the overwhelming majority of the Asian vote in CA (74%) and nationwide (68%).
How ironic is this? That Donald Trump, who talked about "s***hole countries", who made demands for America to "Build the Wall", who implemented an immigration ban on Muslim countries, who introduced a greatly expanded "family separation" policy, who made negative comments about a Hispanic judge and a Muslim Gold Star family, who talked about "his African-American"...did better with nonwhite voters than in 2016 and posted the best performance for a Republican among them in years? And the "slight" swing towards Trump translated into a much more considerable one downballot, with the victories of Young Kim and Michelle Steel.