Perhaps you should try some spelling variations:
nam duoc » nam thuoc, da duoc, dat duoc
cau tren » cu tren, dau tren, ca tren
dang xay » dang van, van xay
thanh va » thanh van, hanh va, thanh ha
va thanh » gia thanh, ban thanh, va tinh
so sach » so sanh, bo sach, co sach
su tien » su kien, su hien, tu tieng
sach ky » sac ky, sach y, sach ty
nam duc » pham duc, nam thuc, nam buoc
xay hoi » xa hoi, tay hoi, cay phoi
ky dang » ky nang, ky danh

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. lieu va ((nam duc) or (nam duoc)) va thanh va ((cau tren) or (su tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky dang xay hoi. lieu va ((nam duc) OR (nam duoc)) va thanh va ((cau tren) OR (su tien)).
• Adding a wildcard symbol may retrieve word variants: so sach ky dang xay hoi. lieu va ((nam duc) or (nam duoc)) va thanh va ((cau tren) or (su tien))*.