Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
toc sach » hoc sach, doc sach, thuoc sach
lang xa » lang ha, dang xay, lang van
danh de » hanh de, dan de, dang de
cua tre » cua te, cuu tre, dua tren
y lang » o lang, _ lang, tay lang
va cao » va cac, va co, va dao
luc va » duc va, tuc va, loc va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y lang xa hoi. lieu va cao ((luc va) or (hoc va)) danh de ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y lang xa hoi. lieu va cao ((luc va) OR (hoc va)) danh de ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y lang xa hoi. lieu va cao ((luc va) or (hoc va)) danh de ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: toc sach y lang xa hoi. lieu va cao ((luc va) or (hoc va)) danh de ((cua tre) OR (cua triet))*.