This question was closed as a duplicate, and the asker said that the suggested question didn't show up in the Related Questions when he asked. So of course I had to try this myself.
I copy/pasted the question title into a new question, and the duplicate didn't show up.
I copy/pasted the question title into the search box, and the duplicate came up 4th in the search results.
Are the searching algorithms different? We need to make it easy for users to find these duplicate questions. It's understandably confusing, especially for new users who don't understand the system.