Perhaps you should try some spelling variations:
nhieu viec » hieu viec, nhien viet
viec cam » viec lam, viec cua, viec va
trinh vi » trinh va, trinh ve, trinh viet
tinh vi » tinh voi, tinh va, dinh vi
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, luc 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 ky ((nang xa) OR (nang ma)) hoi. nhieu viec cam xuc va ((tinh vi) or (trinh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (nang ma)) hoi. nhieu viec cam xuc va ((tinh vi) OR (trinh vi)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang xa) OR (nang ma)) hoi. nhieu viec cam xuc va ((tinh vi) or (trinh vi)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) OR (nang ma)) hoi. nhieu viec cam xuc va ((tinh vi) or (trinh vi)) cua tre*.