Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
danh de » hanh de, dan de, dang de
va danh » va dinh, va dan, va hanh
truc va » thuc va, thuc vat, trung va
van hac » van hoc, van ha, van hai
van bac » van ban, van bao, dan bac
sach ky » sac ky, sach y, sach ty
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
cua tre » cua te, cuu tre, cua triet
de cua » le cua, te cua, dieu cua

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 ((nang ma) OR (sang ma)) hoi. hieu ((van bac) or (van hac)) truc va danh de cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang ma) OR (sang ma)) hoi. hieu ((van bac) OR (van hac)) truc va danh de cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang ma) OR (sang ma)) hoi. hieu ((van bac) or (van hac)) truc va danh de cua tre*".