Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
te sach » toc sach
tang xa » trang xa, tang ma, lang xa
hieu va » lieu va, hieu qua
cam duc » cam xuc, cao duc, nam duoc
dan sai » danh sai, doan sai, dan tai
sach 7 » sach y, sach 2
7 tang » 6 tang
va dan » ca dan, va dao, va dau
cua tu » cua tuc, cua su, cua cu

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 7 tang xa hoi. hieu va ((cam duc) OR (pham duc)) va dan sai ((cua viet) or (cua tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach 7 tang xa hoi. hieu va ((cam duc) OR (pham duc)) va dan sai ((cua viet) OR (cua tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach 7 tang xa hoi. hieu va ((cam duc) OR (pham duc)) va dan sai ((cua viet) or (cua tu))".
• Adding a wildcard symbol may retrieve word variants: te sach 7 tang xa hoi. hieu va ((cam duc) OR (pham duc)) va dan sai ((cua viet) or (cua tu))*.