Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thanh di » thanh doi, thanh de, thanh do
sach ky » sac ky, sach ty, sach kem
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, duc va
di cua » dai cua, doi cua, de cua

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