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

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 ty)) nang xa hoi. hieu van cham duc van hanh ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sac ky) OR (sach ty)) nang xa hoi. hieu van cham duc van hanh ki su triet.
• Adding a wildcard symbol may retrieve word variants: tu ((sac ky) or (sach ty)) nang xa hoi. hieu van cham duc van hanh ki su triet*.