Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
hien hanh » dieu hanh
cua triet » cua viet, su triet, va triet
danh dai » danh dau, danh di, danh sai
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, 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 hanh ((nuoc va) or (duc va)) danh dai ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang xa hoi. hieu hien hanh ((nuoc va) OR (duc va)) danh dai ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang xa hoi. hieu hien hanh ((nuoc va) or (duc va)) danh dai ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang xa hoi. hieu hien hanh ((nuoc va) or (duc va)) danh dai ((cua tre) OR (cua triet))*.