Perhaps you should try some spelling variations:
trinh thiet » trinh viet, trinh thi
thiet luan » thien luan, thi luan, thien quan
luan danh » luan thanh, luan van, luan nang
cho nguoi » cua nguoi
hien huan » hien thuan, tien huan, thien quan
hien quan » thien quan, lien quan, vien quan
hinh hoc » tin hoc, benh hoc

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: giao trinh thiet luan danh cho nguoi viet ((sinh hoc) OR (hinh hoc)) ((hien huan) OR (hien quan))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "giao trinh thiet luan danh cho nguoi viet ((sinh hoc) or (hinh hoc)) ((hien huan) OR (hien quan))~".
• Adding a wildcard symbol may retrieve word variants: giao trinh thiet luan danh cho nguoi viet ((sinh hoc) or (hinh hoc)) ((hien huan) OR (hien quan))*.