Perhaps you should try some spelling variations:
van tuan » van quan, van ban, anh tuan
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac nuoc
cac dac » cac dan, cac dai, cac bac
tuan va » toan va, luan va, quan va
cua tre » cua te, cuu tre, cua triet
va cua » va chua, via cua, ca cua
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: su sach ky nang x hoi. hieu ve ((cac duc) or (cac dac)) van tuan va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang x hoi. hieu ve ((cac duc) OR (cac dac)) van tuan va cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang x hoi. hieu ve ((cac duc) or (cac dac)) van tuan va cua tre*.