Unable to change the theme of specific syntax

I’m trying to port a theme from VSCode, but there is certain uncommon syntax coloring that is uneditable.
The theme looks perfect in all languages able to be previewed, but if I look at a language like Rust or TOML, there is certain syntax that I can’t figure out how to theme:
(I can only attach one image, but things like macros in Rust and “[package]” in TOML are colored the same.)
How would I go about changing these?