I didn't make a new thread. I just used the search features to find the old thread you were looking for. 

I put this image together to walk you through how to use the search function.

First (step one) You have to click on the menu where it says Default, and select 'Advanced' - once you do, you will get a form with multiple search criteria. 

Follow the steps as I ordered them. They should be pretty self-explanatory. in 3 and 4 you can choose to search by days, weeks, months, or years. The red text is just an example. 

Once you have put in all of that, and you get the list of posts that the search pulls up for you, you will notice at the bottom of each post there will be this button:

Click on the button that says "Go to post" - you can control+click (in windows - i don't remember what it is in mac) to open it in a new tab or window, and it will take you to the full thread that contains that particular post. 

Hope this helps in your future searches. And to demonstrate that the feature is not broken. :)