Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hieu quan » hieu qua, lieu quan, thien quan
van hanh » van thanh, ban hanh, van anh
dat duoc » dat nuoc, da duoc, luat duoc
nam duoc » nam thuoc, da duoc, nam moc
cay phoi » cap phoi, tay hoi, cay cho
dang cay » dang xay, dang ca, dang cac
cau tren » cu tren, dau tren, ca tren
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
hanh ve » hanh vi, hanh va, hanh kem
ve cau » ke cau, va cau, ve cac

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 dang cay phoi. hieu quan ((nam duoc) OR (dat duoc)) van hanh ve cau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ky dang cay phoi. hieu quan ((nam duoc) OR (dat duoc)) van hanh ve cau tren".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ky dang cay phoi. hieu quan ((nam duoc) OR (dat duoc)) van hanh ve cau tren*.