as to 怎么去理解

as to 的功能类似于 with regard to， regarding， on the matter of， concerning 等，常用于相当正式的语境中，尤其用于争论和做出决定时。可放于句首或与 wh- 疑问词引导的动词不定式和名词性从句连用

As to the journey， we must decide about that later.
至于旅行，我们必须以后再作决定。

Nobody could decide （ as to ） what to do.
谁也不能决定该做些什么。

A question arose as to who should be the monitor.
关于谁当班长的问题出现了矛盾。

as to 有时用于表示 according to 的含义。例如：

They sorted the eggs as to size and color.
他们按照大小和颜色将鸡蛋进行分类。

关于，至于。。。