Perhaps you should try some spelling variations:
nhieu viec » hieu viec, nhien viet
dang xay » dang van, van xay
viec cam » viec lam, viec cua, viec va
trinh he » trinh han, trinh hoa, trinh thi
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
xay hoi » xa hoi, tay hoi, cay phoi
xuc va » tuc va, luc va, xac va
he cua » le cua, hu cua, de cua
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky dang xay hoi. nhieu viec cam ((xuc va) or (duc va)) trinh he cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky dang xay hoi. nhieu viec cam ((xuc va) OR (duc va)) trinh he cua tu.
• Adding a wildcard symbol may retrieve word variants: so sach ky dang xay hoi. nhieu viec cam ((xuc va) or (duc va)) trinh he cua tu*.