Perhaps you should try some spelling variations:
thuc dan » thuc hanh, thuc vat
thanh ve » hanh ve, thanh va, thanh vien
dang xay » dang van, van xay
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
xay hoi » xa hoi, tay hoi, cay phoi
cua tuc » cua duc, cua tu, cua thuoc
va can » va chan, va cac, va cao
sach o » sach lo, sac o, sach y
o dang » xo dang, do dang, so dang
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: tu sach o dang xay hoi. hieu va can ((thuc dan) OR (hoc dan)) thanh ve ((cua te) or (cua tuc))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach o dang xay hoi. hieu va can ((thuc dan) OR (hoc dan)) thanh ve ((cua te) OR (cua tuc)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach o dang xay hoi. hieu va can ((thuc dan) OR (hoc dan)) thanh ve ((cua te) or (cua tuc))".
• Adding a wildcard symbol may retrieve word variants: tu sach o dang xay hoi. hieu va can ((thuc dan) OR (hoc dan)) thanh ve ((cua te) or (cua tuc))*.