It's only a MySQL/MariaDB issue.
You have 2 ways:
1) increase the EXP given for every mob/quest
Code:
UPDATE t_npc SET a_exp = a_exp * 10;
Code:
UPDATE t_quest SET a_prize_data0 = a_prize_data0 * 10 WHERE a_prize_index0 = 0;
and create the same sql for a_prize_data1, a_prize_data2 etc..
2) reduce your t_exp table (in your data db)
Code:
UPDATE t_exp SET a_exp = a_exp / 10;
Quick solution. This will affect all the EXP related things