Perhaps you should try some spelling variations:
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
cao tuc » dao tuc, cao duc, cao suc
sach ty » sach y, sach thu, xach tay
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
sach tu » sach thu, cach tu, sach uu
di cua » dai cua, doi cua, de cua
va cao » va cac, va co, va dao

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 ty) or (sach tu)) nang xa hoi. hieu va cao tuc ((va danh) OR (va hanh)) di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ty) OR (sach tu)) nang xa hoi. hieu va cao tuc ((va danh) OR (va hanh)) di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ty) or (sach tu)) nang xa hoi. hieu va cao tuc ((va danh) OR (va hanh)) di cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach ty) or (sach tu)) nang xa hoi. hieu va cao tuc ((va danh) OR (va hanh)) di cua tre*.