Perhaps you should try some spelling variations:
sach thue » sach thu, sach tham, cach thuc
danh vai » danh sai, danh va, doanh van
hieu van » hieu va, thien van, lieu va
vai cua » dai cua, hai cua, lai cua
van cam » van nam, van lam, van cau
lang xa » lang ha, dang xay, lang van
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, duc va

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

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