Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan
tu thong » tu thuong, tu tuong, tu trong
thong va » thong cua, truong va, thong qua
lai cua » dai cua, hai cua, lai chau
vai cua » dai cua, hai cua, bai cua
te sach » toc sach
sach tu » sach thu, cach tu, sach ty
hieu va » lieu va, hieu qua
va hoi » xa hoi, va hoc, va hoa
va co » vo co

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 tu thong va hoi. hieu va co ((thuc dan) OR (thuc vat)) hanh ((vai cua) or (lai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach tu thong va hoi. hieu va co ((thuc dan) OR (thuc vat)) hanh ((vai cua) OR (lai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach tu thong va hoi. hieu va co ((thuc dan) OR (thuc vat)) hanh ((vai cua) or (lai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: te sach tu thong va hoi. hieu va co ((thuc dan) OR (thuc vat)) hanh ((vai cua) or (lai cua)) tre*.