Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
cua viet » ca viet, hoa viet, cua vat
hoc hoi » hoc khoi, hoc hoa, hoc noi
hieu ve » hieu va, hieu van
cac tuc » cac toc, cac tu, cac tac
tuc van » thuc van, truc van, tuc va
hanh de » hanh ve, hanh kem
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
ho hoi » hoa hoi, hoi hoi, co hoi
ve cac » va cac, vien cac
de cua » le cua, te cua, dieu cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ky nang ((ho hoi) or (hoc hoi)). hieu ve cac tuc van hanh de cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky nang ((ho hoi) OR (hoc hoi)). hieu ve cac tuc van hanh de cua viet*.