Perhaps you should try some spelling variations:
sach tranh » canh tranh
sach nhah » sach nha, cach nhanh, sach tham
tranh ky » trinh ky, thanh ky, hanh ky
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
ky chi » ky thi, ly chi, ke chi
y khi » ly khi, ky khi, my khi

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 tranh ky chi đong luc ) or ( thu sach nhah y khi đong luc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach tranh ky chi đong luc ) OR ( thu sach nhah y khi đong luc )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach tranh ky chi đong luc ) or ( thu sach nhah y khi đong luc ))*.