Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
tang ha » lang ha, tang ma, trung ha
hieu va » lieu va, hieu qua
ky tang » ky nang, ky dang, kho tang
va cam » va cham, va cac, va cao
tuc va » thuc va, truc va, duc va
ha hoi » hoa hoi, ha noi, xa hoi
van va » van vat, van van, ban va

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

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