Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
cuu tre » cua tre, cau treo
hanh di » hanh vi, hanh de, hang di
te sach » toc sach
hieu ve » hieu va, hieu van
xac va » tac va, ac va, bac va
y hang » ly hang, ty hang, yu hang
tuc va » thuc va, truc va, tuc xa
ve cac » va cac, vien cac
va hoa » van hoa, va hoc, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y hang va hoa. hieu ve cac ((xac va) or (tuc va)) hanh di ((cuu tre) OR (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y hang va hoa. hieu ve cac ((xac va) OR (tuc va)) hanh di ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y hang va hoa. hieu ve cac ((xac va) or (tuc va)) hanh di ((cuu tre) OR (cau tren))".
• Adding a wildcard symbol may retrieve word variants: te sach y hang va hoa. hieu ve cac ((xac va) or (tuc va)) hanh di ((cuu tre) OR (cau tren))*.