Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
sach thu » sach thue, sach thieu, sach tham
trang va » tran van, hang va
hieu van » hieu va, thien van, lieu va
lang xa » lang ha, dang xay, lang van
vat dan » va dan, van dan, vat ran
sai cua » dai cua, hai cua, bai cua
lai cua » dai cua, hai cua, lai chau
van am » van nam, van lam, van dam

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach thu ((trang va) or (lang xa)) hoi. hieu van am thuc vat dan ((sai cua) OR (lai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach thu ((trang va) OR (lang xa)) hoi. hieu van am thuc vat dan ((sai cua) OR (lai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach thu ((trang va) or (lang xa)) hoi. hieu van am thuc vat dan ((sai cua) OR (lai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: thuoc sach thu ((trang va) or (lang xa)) hoi. hieu van am thuc vat dan ((sai cua) OR (lai cua)) tre*.