Q: how to download purchased app?

I'm currently using iTunes 12.4 (32bits, doesn't found the 64bits one)

I have purchased an app, but haven't downloaded it yet.

now, I want to download it through iTunes (I prefer to have a copy on my laptop),

but whenever I click on the download button, iTunes downloads ALL of my other apps!

1. this wastes my bandwidth, thanks a lot

2. this wastes my time, I thought my connection was slow, but then it's just iTunes. thanks again

3. sometimes when it downloads, iTunes hangs, and it hangs my whole laptop. seriously thanks.

back to the question,

how to properly download specifically an app without making iTunes downloads all the other apps?