How to use timestamp column for filtering records in where clause in mysql
AND has higher precedence than OR. Your query, without parentheses, is equivalent to this:

SELECT event_time, user_host, argument 
FROM mysql.general_log 
WHERE (event_time &gt; '2016-08-04 10:50:27' AND user_host LIKE 'vareity_1_1%')
   OR user_host LIKE 'db_tvm%' ;


Try this instead:

SELECT event_time, user_host, argument 
FROM mysql.general_log 
WHERE event_time &gt; '2016-08-04 10:50:27' 
 AND (user_host LIKE 'vareity_1_1%' OR user_host LIKE 'db_tvm%') ;