Can't execute query

SELECT p.*,c.id as cid FROM knowledge_tw as p, knowledge_cate_tw c, knowledge_category_tw as it WHERE (p.id = '21331928' || p.serial_no = '21331928') AND p.id = it.pid AND it.category=c.id AND (p.available='1' or (p.available='0' and p.sdate <= '2018-09-24' AND p.edate >= '2018-09-24')) AND c.available = '1' AND it.category in (������������) GROUP by it.pid

MySQL Error: Unknown column '������������' in 'where clause'

This script cannot continue, terminating.