From his audience and analysis he learned that only 2 of his classmates knew much of anything语法

From his audience and analysis he learned that only 2 of his classmates knew much of anything语法
From his audience and analysis he learned that only 2 of his classmates knew (much) of (anything) about geology.
1.请问这里为什么要用　much ,anything much是修饰不可数名词的,这里是修饰geology吗?　anything 是用于否定句和疑问句的,这里属于否定句和疑问句呀?
2.　that引导的是一个什么从句?