Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
pham duy » pham duc
tang van » dang van, hoang van, trong van
su sach » so sach, vu sach
hanh va » hang va, hanh vi
sach tu » sach thu, cach tu, sach ty
tang ma » mang may
cua tre » cua te, cuu tre, cua triet
va cua » va chua, via cua, ca 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 tu ((tang ma) or (tang van)) hoi. lieu va ((pham duy) or (cham soc)) van hanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach tu ((tang ma) OR (tang van)) hoi. lieu va ((pham duy) OR (cham soc)) van hanh va cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach tu ((tang ma) or (tang van)) hoi. lieu va ((pham duy) or (cham soc)) van hanh va cua tre*.