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