Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hieu van » hieu va, thien van, lieu va
hang di » hang doi, hang vi, hang dien
hanh di » hanh vi, hanh de, danh di
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
van cau » van dau, van hau, van chat
cau tuc » cau truc, cau tu, cau luc
tuc va » thuc va, truc va, tuc xa
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky nang ((x hoi) or (o hoi)). hieu van cau tuc va ((hanh di) OR (hang di)) cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((x hoi) OR (o hoi)). hieu van cau tuc va ((hanh di) OR (hang di)) cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang ((x hoi) or (o hoi)). hieu van cau tuc va ((hanh di) OR (hang di)) cua viet*".