Perhaps you should try some spelling variations:
hien hanh » dieu hanh
hieu hien » bieu hien, dieu hien, chieu chien
dang xay » dang van, van xay
danh du » danh dau, danh tu, dinh du
duoc va » nuoc va, duc va, duoc ma
tuoc va » thuoc va, nuoc va, tuc va
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
lang xa » lang ha, lang van
cua tre » cua te, cuu tre, cua triet
du cua » duy cua, dau cua, dum cua

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 ((lang xa) OR (dang xay)) hoi. hieu hien hanh ((tuoc va) or (duoc va)) danh du cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((lang xa) OR (dang xay)) hoi. hieu hien hanh ((tuoc va) OR (duoc va)) danh du cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((lang xa) OR (dang xay)) hoi. hieu hien hanh ((tuoc va) or (duoc va)) danh du cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ky ((lang xa) OR (dang xay)) hoi. hieu hien hanh ((tuoc va) or (duoc va)) danh du cua tre*.