Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
te sach » toc sach
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
cac tac » cac toc, cac bac, cac dac
dan vat » dang vat, van vat, dan dat
dan va » doan va, dan ca, ban va
x hoi » xa hoi, o hoi, x ho

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 (su sach)) ky nang x hoi. hieu va cac tac da ((dan vat) or (dan va)) cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (su sach)) ky nang x hoi. hieu va cac tac da ((dan vat) OR (dan va)) cua viet.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (su sach)) ky nang x hoi. hieu va cac tac da ((dan vat) or (dan va)) cua viet*.