Unlike most bees, which are after nectar, this one is after something quite different.

跟喜欢取食花蜜的普通蜜蜂不同，这种蜜蜂追踪的东西十分不一样。

She said that I didn't normally compliment her so 'I must be after something'.

她说我一般不会称赞她，所以（我这么做了）就必定有所图。

It's just you don't ever normally give me compliments so you must be after something…

正常情况下你是不会夸我的，所以你一定是有什么目的。

" Harry, you don't reckon You-Know-Who's after something else to turn into a Horcrux? "

“哈利，你不觉得神秘人想要那个东西，是想把它变成魂器吗？”

It's just you don't ever normally give me compliments so you must be after something…

正常情况下你是不会夸我的，所以你一定是有什么目的。

I'm after something more than legacy.

我不只想留下些传统。

" To be after (something)" means to want to get it, to try to do something to get something.

“To be after (something)” 意思是想要得到它， 尝试做某事以得到某物。