Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
luc van » luoc van, luu van, duc van
hanh de » hanh ve, hanh kem
y nang » ky nang, ly nang, v nang
ve cau » ke cau, va cau, ve cac
de cua » le cua, te cua, dieu cua
cua te » cua tu
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y nang x hoi. hieu ((ve cau) or (ket cau)) luc van hanh de cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang x hoi. hieu ((ve cau) OR (ket cau)) luc van hanh de cua te.
• Adding a wildcard symbol may retrieve word variants: toc sach y nang x hoi. hieu ((ve cau) or (ket cau)) luc van hanh de cua te*.