Perhaps you should try some spelling variations:
va trien » va truyen, va thiet, va tuyen
hanh de » hanh ve, hanh kem
truc va » thuc va, thuc vat, trung va
te sach » toc sach
ky dang » ky nang, ky danh
ky lang » ky nang, ky tang, tay lang
qua ca » qua cac, qua cua, qua cai
tuc va » thuc va, tuc xa, duc va
de va » de van, te va, ke va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((ky lang) OR (ky dang)) xa hoi. hieu qua ca ((tuc va) or (truc va)) hanh de va trien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ky lang) OR (ky dang)) xa hoi. hieu qua ca ((tuc va) OR (truc va)) hanh de va trien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ky lang) OR (ky dang)) xa hoi. hieu qua ca ((tuc va) or (truc va)) hanh de va trien".
• Adding a wildcard symbol may retrieve word variants: te sach ((ky lang) OR (ky dang)) xa hoi. hieu qua ca ((tuc va) or (truc va)) hanh de va trien*.