Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, tu cach
te sach » toc sach
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
dao lai » dao lam, dao bai, dao hai
cua tre » cuu tre, cua triet, dua tren
va dat » va dau, va dap, va dai
va dao » ca dao
cua te » cua tu
nuoc » quoc, duoc, ngoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (te sach)) _ lang xa hoi. hieu va dat nuoc va dao lai ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) _ lang xa hoi. hieu va dat nuoc va dao lai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) _ lang xa hoi. hieu va dat nuoc va dao lai ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) _ lang xa hoi. hieu va dat nuoc va dao lai ((cua tre) OR (cua te))*.