Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
toc sach » hoc sach, doc sach, thuoc sach
thanh di » thanh doi, thanh de, thanh do
lang xa » lang ha, dang xay, lang van
van cac » van hac, van cau, dan cac
van bac » van ban, van bao, van hac
xuc van » duc van, luc van, vuc van
cua tre » cua te, cuu tre, cua triet
y lang » o lang, _ lang, tay lang
di cua » dai cua, doi cua, de 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) or (toc sach)) y lang xa hoi. thien ((van cac) OR (van bac)) xuc van thanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) y lang xa hoi. thien ((van cac) OR (van bac)) xuc van thanh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) y lang xa hoi. thien ((van cac) OR (van bac)) xuc van thanh di cua tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) y lang xa hoi. thien ((van cac) OR (van bac)) xuc van thanh di cua tre*.