Perhaps you should try some spelling variations:
cham sat » cham mat, cham soc, khao sat
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
ty lang » tay lang, ty hang, tu lang
hieu vu » hieu va, hieu ve, hieu su
vu cham » va cham, vu kham, tu cham
sat van » sat va, hat van, hoat van
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((ty lang) or (ty xang)) xa hoi. hieu vu cham sat van hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ty lang) OR (ty xang)) xa hoi. hieu vu cham sat van hanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ((ty lang) or (ty xang)) xa hoi. hieu vu cham sat van hanh di cua tre*.