Perhaps you should try some spelling variations:
bieu hien » dieu hien, dieu khien, bien phien
hieu hien » dieu hien, chieu chien, dieu khien
danh dai » danh dau, danh di, danh sai
nang ma » tang ma, sang ma, nang cao
tuoc va » thuoc va, nuoc va, duoc va
cua tre » cua te, cuu tre, cua triet
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
ma hoi » mai hoi, xa hoi, ma hoa

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

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