Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh tai » thanh tai, hang tai, han tai
thuc dan » thuc hanh, hoc dan, thuc vat
su sach » so sach
tai cua » thai cua, tai cuc, tri cua
van cac » van hac, van cau, van bac
nang xa » nang x, lang xa, nang ma
vu sach » vu bach, vu khach
luc va » duc va, tuc va, loc va
cua te » cua tu

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) OR (vu sach)) ky nang xa hoi. hieu van cac ((luc va) or (thuc dan)) hanh tai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) ky nang xa hoi. hieu van cac ((luc va) OR (thuc dan)) hanh tai cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (vu sach)) ky nang xa hoi. hieu van cac ((luc va) or (thuc dan)) hanh tai cua te*".