>>If you're looking for the exact phrase to be found (different type of search), then should not it be
>>
>>select ... from Threads where Thread.Notes like '%' + @Phrase + '%' - exact phrase ?
>>
>>(There is, of course, a problem with this approach, as it may result in false positives).
>
>This is not optimized. It has to be a full text indexing syntax in order to be fast.

Check Relevant MSDN thread

Not sure it's the best solution, I'll continue looking.