Because JIRA search just sucks that bad. We need extra help.
Here's an idea. When you name a ticket for a task that you need to do in your project, pick a very unique name that you can always remember later.
For example, a web form:
Business Maintenance Form reloaded
There are two files here, please pick one and kill the other.
Then when you need to find the issue ticket again, it's simple to search for your 'keyword'.