Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
dinh vit » dinh viet, dinh vi, dinh vat
hoc sac » hoc sach, hoc cac, hoc mac
cao hoi » cau hoi, co hoi, cao hoc
van cau » van dau, van hau, van chat
ca tren » cau tren, cu tren, la tren
sac ky » cac ky, sai ky
luc va » tuc va, loc va
vit ca » viet ca, viet cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sac ky nang cao hoi. hieu van cau ((luc va) or (duc va)) dinh vit ca tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sac ky nang cao hoi. hieu van cau ((luc va) OR (duc va)) dinh vit ca tren.
• Adding a wildcard symbol may retrieve word variants: hoc sac ky nang cao hoi. hieu van cau ((luc va) or (duc va)) dinh vit ca tren*.