Perhaps you should try some spelling variations:
van luat » dan luat, va luat, van luan
van xuat » san xuat, va xuat, phan xuat
vat dinh » va dinh, van dinh, vat sinh
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
dinh di » dinh du, dinh vi, danh di
ma hoi » mai hoi, xa hoi, ma hoa
di cua » dai cua, doi cua, de cua

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) or (thu hoach)) ky nang ma hoi. hieu ((van luat) OR (van xuat)) thuc vat dinh di cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu hoach)) ky nang ma hoi. hieu ((van luat) OR (van xuat)) thuc vat dinh di cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu hoach)) ky nang ma hoi. hieu ((van luat) OR (van xuat)) thuc vat dinh di cua vat".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu hoach)) ky nang ma hoi. hieu ((van luat) OR (van xuat)) thuc vat dinh di cua vat*.