how to make tabpage fill to right

[amasahara]

i set font size of tabpage header more bigger but width not resize width to right base tabpage content. my custom code in form_load

tabControl.Font = new Font("Times New Roman", 20, FontStyle.Bold);
tabControl.SizeMode = TabSizeMode.FillToRight;
tabControl.DrawMode = TabDrawMode.OwnerDrawFixed;
tabControl.ItemSize = new Size(tabCauHoi.Width / tabCauHoi.TabCount, 70);