Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
co sach » bo sach, cuon sach, hoc sach
vuc van » duc van, luc van, thuc van
sach ty » sach y, sach tu, sach thu
ve cham » va cham, ve chat, vu cham
ty sang » ty xang, ty hang, duy sang
cuu tre » cua tre, cau tren, cau treo
ve cac » va cac, vien cac
ma hoi » mai hoi, ma hoa, me hoi
vi cuu » vi luu, vinh cuu

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

• Performing a fuzzy search may retrieve terms with similar spellings: co sach ty sang ((ma hoi) or (xa hoi)). hieu ((ve cham) or (ve cac)) vuc van hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ty sang ((ma hoi) OR (xa hoi)). hieu ((ve cham) OR (ve cac)) vuc van hanh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: co sach ty sang ((ma hoi) or (xa hoi)). hieu ((ve cham) or (ve cac)) vuc van hanh vi cuu tre*.