Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
sang tao » hang tai
tinh di » tinh doi, trinh di, tinh da
va tinh » may tinh
truc va » thuc va, thuc vat, trung va
hieu va » lieu va, hieu qua
tu sach » thu sach, su sach, te sach
sang ma » tang ma, nang ma, mang may
cua tre » cua te, cuu tre, cua triet
di cua » dai cua, doi cua, de cua

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: tu sach y ((sang ma) OR (sang tao)) hoa. ((hieu van) OR (hieu va)) cau truc va tinh di cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((sang ma) OR (sang tao)) hoa. ((hieu van) or (hieu va)) cau truc va tinh di cua tre~".
• Adding a wildcard symbol may retrieve word variants: tu sach y ((sang ma) OR (sang tao)) hoa. ((hieu van) or (hieu va)) cau truc va tinh di cua tre*.