Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
sach duoc » sach nuoc, sach dao, sach dung
bach duoc » bach tuoc, ban duoc, gach duoi
thanh ve » hanh ve, thanh va, thanh vien
cua tre » cua te, cuu tre, cua triet
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
sac ky » cac ky, sai ky
ve cua » le cua, de cua, te cua
tu sac » tu sach, tu cac, tu san

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

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