Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
mai khoi » mai khoa, tai khoa, cac khoi
trinh di » trinh do, trinh dien, trinh dinh
thu sach » thuat sach, thuoc sach, thu hoach
va trinh » van trinh, va tinh, lap trinh
vien dao » vien dai, vien da, vien cao
dao tuc » dao duc
tu sach » su sach, te sach, tu cach
mai hoi » dai hoi, lai hoi, mai doi
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, truc va, tuc xa
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 sach)) ky nang ((mai hoi) or (mai khoi)). hieu vien dao tuc va trinh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang ((mai hoi) OR (mai khoi)). hieu vien dao tuc va trinh di cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky nang ((mai hoi) or (mai khoi)). hieu vien dao tuc va trinh di cua tre*".