Perhaps you should try some spelling variations:
tang thanh » dang thanh, trung thanh, hoang thanh
thanh vai » thanh hai, thanh van, thanh tai
hieu van » hieu va, thien van, lieu va
duc tang » duc thang, duc tan, tuc tang
vai cua » dai cua, hai cua, lai cua
bao duc » dao duc, bao luc, cao duc
van bao » van ban, van dao
te sach » toc sach
su sach » so sach, vu sach
ly nang » ky nang, ly hang, ly vang
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, v nang, may nang
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: ((te sach) or (su sach)) ((y nang) OR (ly nang)) x hoi. hieu van bao duc tang thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (su sach)) ((y nang) OR (ly nang)) x hoi. hieu van bao duc tang thanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (su sach)) ((y nang) OR (ly nang)) x hoi. hieu van bao duc tang thanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (su sach)) ((y nang) OR (ly nang)) x hoi. hieu van bao duc tang thanh vai cua tre*.