Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
sach tham » sach nha
hanh hai » thanh hai, nhanh hai, hang hai
vien cac » vien bach, vien dai, vien da
sach thu » sach thue, sach thieu, cach thuc
hai cua » thai cua, dai cua, hoi cua
va hanh » van hanh, va thanh, va danh
cac tuc » cac toc, cac tu, cac tac
lang xa » lang ha, dang xay, lang van
mang xa » mang may, dang xay, mang cua
tuc va » thuc va, truc va, tuc xa
cua tu » cua tuc, cua su, cua cu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach thu) OR (sach tham)) ((mang xa) or (lang xa)) hoi. hieu vien cac tuc va hanh hai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach thu) OR (sach tham)) ((mang xa) OR (lang xa)) hoi. hieu vien cac tuc va hanh hai cua tu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach thu) OR (sach tham)) ((mang xa) or (lang xa)) hoi. hieu vien cac tuc va hanh hai cua tu".
• Adding a wildcard symbol may retrieve word variants: tu ((sach thu) OR (sach tham)) ((mang xa) or (lang xa)) hoi. hieu vien cac tuc va hanh hai cua tu*.