Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hanh di » hanh vi, hanh de, hang di
luu van » cuu van, luan van, luu hanh
luc van » luoc van, duc van, luc va
hoc sac » hoc sach, hoc cac, hoc mac
vu cham » va cham, vu kham, tu cham
nang xa » nang x, lang xa, nang ma
sac ky » cac ky, sai ky
di cua » dai cua, doi cua, de cua
ve cac » va cac, vien cac

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 xa hoi. hieu ((vu cham) or (ve cac)) ((luc van) OR (luu van)) hanh di cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sac ky nang xa hoi. hieu ((vu cham) OR (ve cac)) ((luc van) OR (luu van)) hanh di cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sac ky nang xa hoi. hieu ((vu cham) or (ve cac)) ((luc van) OR (luu van)) hanh di cua viet".
• Adding a wildcard symbol may retrieve word variants: hoc sac ky nang xa hoi. hieu ((vu cham) or (ve cac)) ((luc van) OR (luu van)) hanh di cua viet*.