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
toc sach » hoc sach, doc sach, thuoc sach
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
cua tre » cua te, cuu tre, cua triet
su sach » so sach, vu sach
y nang » ky nang, ly nang, v 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 (toc sach))) or (su sach)) y 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 (toc sach))) OR (su sach)) y 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 (toc sach))) or (su sach)) y nang x hoi. hieu van bao duc tang thanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((((te sach) OR (toc sach))) or (su sach)) y nang x hoi. hieu van bao duc tang thanh vai cua tre*.