Adding two contextual filters (Content : nid) I want to display two type of contents : News and Events. 
So I added them in the filters criteria. This works great. 
Now I want them to be further filtered on the basis of the category the News and Events lie in. For example, I only want to display News and Events having category "xyz".
So what I did is, I added a reverse relationship for News and a contextual filter of Content : nid having the relationship that I made. This works OK and shows the desired news. 
BUT
when I try to add another relationship and contextual filter, all the data disappears. 

Any help in this regard would be highly appreciated! 
Thanks! 

Here are the sceenshots :
When you add two contextual filters, views expects to receive two contextual filters. Currently in your preview area you are only supplying one (you need to add the second contextual filter (article filter: content nid) as well and separate them with a /). If you use the Provide nid from url filters it might work on the page, but in the preview you still need to provide both values.

However this is not the correct way to proceed, you should be doing something like this:

Since your block should only show on the industry page, you need to obtain the nid of the industry you are looking at. Use one contextual filter, and fill if with the default value: content id from url. This will load the industry nid you are looking at.

Then, since this industry has two different content types attached, you need to add relations to both of them. If the content relates to the industry (likely scenario) you should be using the reversed relationship as you currently do. If the industry links to the content, you should use the non-reversed relationship. I guess you did this step right.

The biggest problem here is that you do not use your relationships for the filters. So Your content &gt; -365 days is not filtering the articles or news, but applies to the industry. The same happens with your content type. You want to display nodes of articles or news, but instead you filter the node you are looking at to be of those types (which fails as it an industry). 

So edit your filters and set them to use the related content's fields.
You can only set one relation for each filter, so you'd have to create each filter twice (once for articles and once for news). Then use the drop down button above the Filters section to create an And / or group and drag the items in a way so the type is of article or news.