Extract raw content from a website

I know there are many tools to do this but i want to build one on my own, so please no software recommendation.

There is a website like this : http://ift.tt/2BmRW87;

If you clicked into every items, there is more infos about that item. My goal is to go through every item in this page and extract those item.

So the question is when i use "Inspector" on each item i could see the html file and the corresponding information. But when i tried to download the whole page by using "Save As", i couldnt find those element anymore.

Is there any programmatical way to retrieve all these information ? What is the best approach to do this kind of task, assuming i need to programm it myself ?