Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
hien bach » vien bach, thien hach, hien hanh
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
duoc va » duc va, duoc ma, duong va
danh du » danh dau, danh tu, dinh du
cuu tre » cau tren, cau treo
cua tre » cua te, cua triet, dua tren

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang xa hoi. hieu hien bach ((nuoc va) or (duoc va)) danh du ((cuu tre) OR (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang xa hoi. hieu hien bach ((nuoc va) OR (duoc va)) danh du ((cuu tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang xa hoi. hieu hien bach ((nuoc va) or (duoc va)) danh du ((cuu tre) OR (cua tre))".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang xa hoi. hieu hien bach ((nuoc va) or (duoc va)) danh du ((cuu tre) OR (cua tre))*.