Perhaps you should try some spelling variations:
tan hanh » tan thanh, tang hanh, toan hanh
sach ly » sach lo, sach ty, sach hay
hieu va » lieu va, hieu qua
gia duc » giao duc, gia muc, gia thuc
vai cua » dai cua, hai cua, lai cua
hoi cua » hoi chuc
va gia » va giai
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((sach ly) OR (sach y)) nang x hoi. hieu va gia duc tan hanh ((vai cua) or (hoi cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ly) OR (sach y)) nang x hoi. hieu va gia duc tan hanh ((vai cua) OR (hoi cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ly) OR (sach y)) nang x hoi. hieu va gia duc tan hanh ((vai cua) or (hoi cua)) tre".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ly) OR (sach y)) nang x hoi. hieu va gia duc tan hanh ((vai cua) or (hoi cua)) tre*.