Perhaps you should try some spelling variations:
nhieu viec » hieu viec, nhien viet
thuc cao » thuoc cao, thuc co, thuc can
sach thu » sach thue, sach thieu, sach tham
dan thuc » dan toc, am thuc
viec dan » viec dang, viec ban, viec dat
cao dan » cao dang, cao danh, cac dan
cua tre » cua te, cuu tre, cua triet
sach ty » sach y, sach tu, xach tay
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
dan vi » doan vi, don vi, dan 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: te ((sach ty) OR (sach thu)) ((nang xa) or (nang ma)) hoi. nhieu viec dan thuc cao dan vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ty) OR (sach thu)) ((nang xa) OR (nang ma)) hoi. nhieu viec dan thuc cao dan vi cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ty) OR (sach thu)) ((nang xa) or (nang ma)) hoi. nhieu viec dan thuc cao dan vi cua tre*".