If used effectively, Communities could be your 24hr Knowledge center, and Conversations are most effective when started in the right areas, notifying the right people.
Own the thread
When you post a Question, it is like opening a Service request which you will own through it's lifecycle.
As experts look into your query, more and more data will be exchanged, analysis, details offered. Make sure you provide the necessary details, screenshots, logs, or even reminders, anything needed to make your case easily understood. Your enthusiasm to follow through will breed energy around the thread.
Continue to research
Maybe a direct clue or a piece of the puzzle is lying in similar Discussions and documents created in the forums. Infact you would be the best person pursuing your own cause, sometimes even before you get to be fully understood by others. See for eg. this discussion on a Ubuntu Server instance which ultimately, as it turned out, got self answered by the requestor. Check out the More Like This widget along every thread which provide you similar discussions supplementing your quest.
Appreciating and acknowledging a Correct or helpful answer not only encourages people on the thread but also helps all users like you by highlighting the right solution.
There could also be an opportunity to make new friends in the process, a great note to Close your case with.
As we'd all agree, whatever may be the business, at the end of the day, it always runs on positive relationships