Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
trong vang » trong dang, trong tang, trong bang
hoc thieu » toc thieu, hoc hien
trung van » truong van, trung va, trung tuan
trong van » trong cac
vang hang » van hang, hang hang, nang hang
hang cau » hang dau, hang ca, nhung cau

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sach - thanh ((trung van) OR (trong van)) dung trong vang hang cau~.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sach - thanh ((trung van) or (trong van)) dung trong vang hang cau*.