Perhaps you should try some spelling variations:
tinh hoc » sinh hoc, tin hoc, hinh hoc
cua tre » cua te, cuu tre, cua triet
va danh » va dinh, va dan, dia danh
va hanh » van hanh, va thanh, ban hanh
va tinh » may tinh
hieu va » lieu va, hieu qua
tay hoi » tay ho, tao hoi, tay thai
sac ky » cac ky, sai ky
ta hoi » tao hoi, tai hoi, tan hoi
ky anh » ky danh, ly anh, ty anh
vi cua » vai cua, di cua
tu sac » tu sach, tu cac, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky anh ((ta hoi) OR (tay hoi)). hieu va tinh hoc ((va hanh) or (va danh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky anh ((ta hoi) OR (tay hoi)). hieu va tinh hoc ((va hanh) OR (va danh)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky anh ((ta hoi) OR (tay hoi)). hieu va tinh hoc ((va hanh) or (va danh)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sac ky anh ((ta hoi) OR (tay hoi)). hieu va tinh hoc ((va hanh) or (va danh)) vi cua tre*.