Perhaps you should try some spelling variations:
ve triet » va trien, su triet
hoc sac » hoc sach, hoc cac, hoc mac
cao hoi » cau hoi, co hoi, cao hoc
van cam » van lam, van cau, van dam
va hanh » van hanh, va thanh, va danh
sac ky » cac ky, sai ky
tuc va » thuc va, truc va, tuc xa
cua tu » cua tuc, cua su, cua cu

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 cam) OR (van nam)) tuc va hanh vi ((cua tu) or (ve triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sac ky nang cao hoi. hieu ((van cam) OR (van nam)) tuc va hanh vi ((cua tu) OR (ve triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sac ky nang cao hoi. hieu ((van cam) OR (van nam)) tuc va hanh vi ((cua tu) or (ve triet))".
• Adding a wildcard symbol may retrieve word variants: hoc sac ky nang cao hoi. hieu ((van cam) OR (van nam)) tuc va hanh vi ((cua tu) or (ve triet))*.