I was searching for issues I had seen on a Moodle 1.9 site where the R Count of a quiz item analysis did not match up to the total attempts that had been made on an assessment. The assessment in question had 70 attempts but only 55 were represented in the R Count, which for statistics makes a slight issue with numbers adding up and being useful.
Searching at Moodle.org using the regular field wasn’t that useful (there are over 100,000 discussions in the Using Moodle forums), but it did lead me to this: https://moodle.org/mod/forum/search.php?search=&id=5
After refining my search for a specific forum (quiz) and choosing a date range (to try and narrow it down to pre 2.0 discussions) I was able to find some handy information that teacher attempts might also be included (mystery partially solved). In any event, the advanced search is available and extremely helpful as the forums continue to grow and grow. Enjoy!
Advanced Forum Search: https://moodle.org/mod/forum/search.php?search=&id=5