Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hanh vai » hanh vi, hanh va, hanh tai
dan hanh » dang hanh, dan khanh, dan thanh
thuc dan » thuc hanh, hoc dan, thuc vat
sach ky » sac ky, sach y, sach ty
hoa doi » hoa dai, xoa doi, hoa duoc
hoc doi » hoc dai, hoc noi, hoc moi
ky lang » ky nang, ky dang, ky tang
su tien » su kien, su hien, tu tieng
va nam » van nam, ha nam, va nay
le nam » ly nam, he nam, le na
vai su » va su, van su, lai su

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 ky lang ((hoa doi) OR (hoc doi)). hieu ((va nam) or (le nam)) thuc dan hanh vai su tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ky lang ((hoa doi) OR (hoc doi)). hieu ((va nam) OR (le nam)) thuc dan hanh vai su tien*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ky lang ((hoa doi) OR (hoc doi)). hieu ((va nam) or (le nam)) thuc dan hanh vai su tien*".