Perhaps you should try some spelling variations:
thanh dat » thanh san, thanh hai, thanh van
toc sach » hoc sach, doc sach, thuoc sach
su triet » su viet, ve triet
va thanh » gia thanh, ban thanh, va tinh
su tien » su kien, su hien, tu tieng
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
v nang » va nang, vu nang, van nang
ve cac » va cac, vien cac
du va » dau va, tu va, su va

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: ((te sach) OR (toc sach)) v nang ma hoa. hieu ve cac du va thanh dat ((su triet) OR (su tien))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) v nang ma hoa. hieu ve cac du va thanh dat ((su triet) OR (su tien))~".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) v nang ma hoa. hieu ve cac du va thanh dat ((su triet) OR (su tien))*.