Perhaps you should try some spelling variations:
danh doi » danh di, thanh doi, dung doi
thuc dan » thuc hanh, hoc dan, thuc vat
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
doi cua » dai cua, hoi cua
hieu va » lieu va, hieu qua
va cao » va cac, va co, va dao
tuc va » thuc va, truc va, tuc xa
cua te » cua tu
x hoi » o hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky nang ((x hoi) OR (xa hoi)). hieu va cao ((tuc va) or (thuc dan)) danh doi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky nang ((x hoi) OR (xa hoi)). hieu va cao ((tuc va) OR (thuc dan)) danh doi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky nang ((x hoi) OR (xa hoi)). hieu va cao ((tuc va) or (thuc dan)) danh doi cua te".
• Adding a wildcard symbol may retrieve word variants: vu sach ky nang ((x hoi) OR (xa hoi)). hieu va cao ((tuc va) or (thuc dan)) danh doi cua te*.