Perhaps you should try some spelling variations:
van cham » van chat, van tham, va cham
cham duc » pham duc, cham soc, pham duy
su triet » su tien, ve triet
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
duc van » duc va, duc tan, duc manh
su viet » so viet
nang xa » nang x, lang xa, nang ma
sac ky » cac ky, sai ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sac ky) or (sach y)) nang xa hoi. hieu van cham duc van hanh vi ((su triet) OR (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sac ky) OR (sach y)) nang xa hoi. hieu van cham duc van hanh vi ((su triet) OR (su viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sac ky) or (sach y)) nang xa hoi. hieu van cham duc van hanh vi ((su triet) OR (su viet))".
• Adding a wildcard symbol may retrieve word variants: tu ((sac ky) or (sach y)) nang xa hoi. hieu van cham duc van hanh vi ((su triet) OR (su viet))*.