Wushu Tao
(https://www.wushu-tao.com)
Writing sheet of the character : - xū 虚 (Vide / inoccupé / vacant / faux / faible / fragile)
 
For more informations about this character and his pronunciation, consult this page :
https://www.wushu-tao.com/page_ac_liste_car.php