SharePoint 2013 custom search Result Type for "Documents" not showing up as option

Question

I'm trying to create a custom search Result Type called "Documents" that will filter to MS Office filetypes and PDF's.
However, when I perform a search, although many of these types of files show up in the results, I don't have "Documents" as a Result Type option.
Here are the steps I'm following:
From my Enterprise Search Center subsite: Site Settings > Manage Result Types.
New Result Type.
Name: Documents
Source: Documents (System) - this out-of-the-box Result Source appears to cover the filetypes I need.
Types of content: I've tried leaving it blank (to match all content) and specifically picking the types I want.
What should these results look like? Office Document Item.
Check Optimize for frequent use.
Save.
I then go back to my search center and search for a common keyword. Many in-scope file show up in the search results. However, under Result Type, I don't see "Documents," even if I click "SHOW MORE."
Please advise.
Thanks.
Brad

Answer 1

@Mikael As you say, to display the exact results when we click a result source, we should implement logic code to check whether item should be displayed. I have followed steps nearly the same as the topic owner but I saw nothing different between Everything
and my custom Result Type.
Here are the steps I'm following:
Create a custom result type, named Job, and specify a custom display template for it.
Set its condition to filter list items that have JobName site column ( JobName is site column's managed property) equal of any "IT" or "Doctor".
I search for "Perter", it returns 5  items with Everything. I expect that it should return 3 items since only those items contain JobName site column.
Search is fun but rather headache sometimes, give me advise please :)
Thanks,
Hoan.