Don’t read such books as are not worth reading.这里的as能不能换成which/that?

不可以的

不可以哦 这是定语从句
当先行词前有such, so, as时，关系词应当用as。如：
A wise man seldom talks about such things as he doesn’t understand.
He spoke in such easy English as everybody could understand.
At this time of the day, all buses and trolleys have to carry as many passengers as they can.
It is so easy a book as every schoolboy can read.
Let’s discuss such things as we can talk of freely.
这句话意思是 不要读那些不值得读得书。as 在这里作主语引导定语从句。

不可以。当先行词被such修饰时，其后的关系代词只能用as。

可以换，但是意思变了。
第一句是原因状语：不要读这种书，因为那不值得
第二句就是定语从句了：不要读不值得读的书。

这里的as是引导的定从,不能换成which/that.因为当先行词前有such时,定从就只能用as 引导.句意:不要读这些不值得读的书.such + 形+ 名+ that从句,that 引导结果状从,"如此...以致于..."They are such lovely children...

这是 such as的搭配 不能换

such as在这里是绝配，不能换。 除非是将such也一起换掉。