Everybody can help with the searching side of this issue
If the title of the duplicate question was added as a comment to the original question, that would help with the searching issue. The alternate wording of the same question would appear on the same page and possibly come up as a search result.
Suggestion for site programmers
If two questions are really exact duplicates, no reason why the answers could not be merged on one page (with respective votes in tact), and the duplicate title added on as some sort of alternative/secondary title for searching purposes.