Perhaps you should try some spelling variations:
nhieu viec » hieu viec, nhien viet
toc sach » hoc sach, doc sach, thuoc sach
thuc cao » thuoc cao, thuc co, thuc can
dan thuc » dan toc, am thuc
viec dan » viec dang, viec ban, viec dat
cau theo » cau thi, cau tao
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
cao dan » cao dang, cao danh, cac dan
cuu tre » cua tre, cau tren, cau treo
dan va » doan va, dan ca, ban va
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ty nang ((x hoi) OR (o hoi)). nhieu viec dan thuc cao dan va ((cuu tre) or (cau theo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty nang ((x hoi) OR (o hoi)). nhieu viec dan thuc cao dan va ((cuu tre) OR (cau theo)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty nang ((x hoi) OR (o hoi)). nhieu viec dan thuc cao dan va ((cuu tre) or (cau theo))".
• Adding a wildcard symbol may retrieve word variants: toc sach ty nang ((x hoi) OR (o hoi)). nhieu viec dan thuc cao dan va ((cuu tre) or (cau theo))*.