Perhaps you should try some spelling variations:
thanh dat » thanh san, thanh hai, thanh van
te sach » toc sach
dat cua » dai cua, day cua, mat cua
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
nang ma » sang ma, nang cao, mang may
tang ma » mang may, tang van
ve cac » va cac, vien cac
du va » dau va, tu va, vu va
su va » su van, tu va

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 ((nang ma) OR (tang ma)) hoa. hieu ve cac ((du va) or (su va)) thanh dat cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y ((nang ma) OR (tang ma)) hoa. hieu ve cac ((du va) OR (su va)) thanh dat cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y ((nang ma) OR (tang ma)) hoa. hieu ve cac ((du va) or (su va)) thanh dat cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach y ((nang ma) OR (tang ma)) hoa. hieu ve cac ((du va) or (su va)) thanh dat cua tre*.