Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
hien cac » thien cac, vien cac, hieu cac
cac truc » cau truc, cac tru, cac trung
hanh de » hanh ve
truc va » thuc va, thuc vat, trung va
su sach » vu sach
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
so sach » so sanh, bo sach, co sach
cua tre » cua te, cuu tre, cua triet

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

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