Perhaps you should try some spelling variations:
dat thanh » dao thanh, dat khanh, dang thanh
ban hang » ngan hang
vu sach » vu bach, su sach, vu khach
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ve cam » ve cham, va cam, ve cai
di cua » dai cua, doi cua, de cua
ve cac » va cac, vien cac
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach y nang x hoi. hieu ((ve cam) OR (ve cac)) thuc ((dat thanh) or (ban hang)) di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach y nang x hoi. hieu ((ve cam) OR (ve cac)) thuc ((dat thanh) OR (ban hang)) di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach y nang x hoi. hieu ((ve cam) OR (ve cac)) thuc ((dat thanh) or (ban hang)) di cua tre".
• Adding a wildcard symbol may retrieve word variants: vu sach y nang x hoi. hieu ((ve cam) OR (ve cac)) thuc ((dat thanh) or (ban hang)) di cua tre*.