How many users who have received a low cool vote have also received at least 1 low cool vote for some of their reviews?
low cool vote for user refers to user_votes_cool = 'Low';  low cool vote for review refers to review_votes_cool = 'Low'
SELECT COUNT(DISTINCT T1.user_id) FROM Users AS T1 INNER JOIN Reviews AS T2 ON T1.user_id = T2.user_id WHERE T1.user_votes_cool = 'Low' AND T2.review_votes_cool = 'Low'