Perhaps you should try some spelling variations:
thu sach » thuat sach, thuoc sach, thu hoach
kho tang » cao tang
hanh lai » hanh lam, hanh tai, thanh lap
tu sach » su sach, te sach, tu cach
truc va » thuc va, thuc vat, trung va
lai cua » dai cua, hai cua, lai chau
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
tang ma » mang may, tang van
ve cam » ve cham, ve cac, va cam
xuc va » duc va, tuc va, luc va
ma hoi » mai hoi, xa hoi, ma hoa

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) OR (thu sach)) kho tang ma hoi. hieu ve cam ((xuc va) or (truc va)) hanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) kho tang ma hoi. hieu ve cam ((xuc va) OR (truc va)) hanh lai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) kho tang ma hoi. hieu ve cam ((xuc va) or (truc va)) hanh lai cua tre*".