Perhaps you should try some spelling variations:
nhieu vien » nhieu viec, nhiet dien, thieu nien
vien cac » vien bach, vien dai, vien da
trinh ve » trinh he, trinh va, trinh vi
va trinh » van trinh, va tinh, lap trinh
cua tre » cua te, cua triet, dua tren
cac dac » cac dan, cac dai, cac bac
tu sach » thu sach, te sach, tu cach
nang ma » tang ma, sang ma, nang cao
su sach » so sach, vu sach
cuu tre » cau tren, cau treo
ma hoi » mai hoi, xa hoi, ma hoa
dac va » duc va, day va, dat va

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 (su sach)) ky nang ma hoi. nhieu vien cac dac va trinh ve ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky nang ma hoi. nhieu vien cac dac va trinh ve ((cua tre) OR (cuu tre))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky nang ma hoi. nhieu vien cac dac va trinh ve ((cua tre) OR (cuu tre))*".