Perhaps you should try some spelling variations:
sach tay » sach hay, sach nay, sach tai
xach tay » canh tay
lang van » dang van, tang van, hoang van
nam thuc » nam thuoc, am thuc, nam tu
dang de » dang deo, dung de, dang do
va dang » van dang, va nang, va lang
hieu ve » hieu va, hieu van
van hoe » van hoa, van hoc, van hieu
de cua » le cua, te cua, dieu cua
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: co ((sach tay) OR (xach tay)) lang van hoe. hieu ve ((nam thuc) or (nam thu)) va dang de cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co ((sach tay) OR (xach tay)) lang van hoe. hieu ve ((nam thuc) OR (nam thu)) va dang de cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co ((sach tay) OR (xach tay)) lang van hoe. hieu ve ((nam thuc) or (nam thu)) va dang de cua te".
• Adding a wildcard symbol may retrieve word variants: co ((sach tay) OR (xach tay)) lang van hoe. hieu ve ((nam thuc) or (nam thu)) va dang de cua te*.