Perhaps you should try some spelling variations:
dau tieng » dau tien, cau tieng, day tieng
van hanh » van thanh, ban hanh, van anh
hanh dem » hanh kem, hanh de, thanh dam
sach ty » sach y, sach thu, xach tay
sach tu » sach thu, cach tu, sach uu
nang xa » nang x, lang xa, nang ma
tuc van » thuc van, truc van, tuc va
va cau » van cau, va dau, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat ((sach ty) OR (sach tu)) nang xa hoi. lieu ((va cau) or (va cac)) tuc van hanh dem dau tieng~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((sach ty) OR (sach tu)) nang xa hoi. lieu ((va cau) OR (va cac)) tuc van hanh dem dau tieng.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((sach ty) OR (sach tu)) nang xa hoi. lieu ((va cau) or (va cac)) tuc van hanh dem dau tieng".
• Adding a wildcard symbol may retrieve word variants: thuat ((sach ty) OR (sach tu)) nang xa hoi. lieu ((va cau) or (va cac)) tuc van hanh dem dau tieng*.