Perhaps you should try some spelling variations:
nhieu viec » hieu viec, nhien viet
tinh hoc » sinh hoc, hinh hoc, trinh hoa
viec lam » viec va
tu sach » thu sach, su sach, te sach
cuu tre » cau tren, cau treo
tin hoc » sinh hoc
sach ky » sac ky, sach y, sach ty
lam tuc » lam thuoc, lam truoc, luat tuc
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
cua tre » cua te, cua triet, dua tren
tuc va » thuc va, truc va, tuc xa

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 ky tang xa hoi. nhieu viec lam tuc va ((tinh hoc) or (tin hoc)) ((cuu tre) OR (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky tang xa hoi. nhieu viec lam tuc va ((tinh hoc) OR (tin hoc)) ((cuu tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky tang xa hoi. nhieu viec lam tuc va ((tinh hoc) or (tin hoc)) ((cuu tre) OR (cua tre))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky tang xa hoi. nhieu viec lam tuc va ((tinh hoc) or (tin hoc)) ((cuu tre) OR (cua tre))*.