Perhaps you should try some spelling variations:
sach tru » sach truc, sach thu, sach tu
tru nang » tra nang, tri nang, truc nano
hieu van » hieu va, thien van, hieu ve
te sach » toc sach
nang xa » nang x, lang xa, nang ma
cuc ban » cua ban, cac ban, cuu ban
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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 tru nang xa hoi. ((hieu van) OR (lieu va)) cam ((cuc ban) or (cuu van)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach tru nang xa hoi. ((hieu van) OR (lieu va)) cam ((cuc ban) OR (cuu van)) hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach tru nang xa hoi. ((hieu van) OR (lieu va)) cam ((cuc ban) or (cuu van)) hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach tru nang xa hoi. ((hieu van) OR (lieu va)) cam ((cuc ban) or (cuu van)) hanh vi cua tre*.