Perhaps you should try some spelling variations:
cua triet » cua viet, va triet
su triet » su viet, su tien, ve triet
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
hanh hai » thanh hai, nhanh hai, hang hai
tu sach » thu sach, su sach, te sach
duc van » duc va, duc tan, duc manh
sach ky » sac ky, sach y, sach ty
van cau » van dau, van hau, van chat
lang xa » lang ha, dang xay, lang van
cau duc » cao duc, cau luc, chu duc

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ky ((nang x) or (lang xa)) hoi. hieu van cau duc van hanh hai ((cua triet) OR (su triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang x) OR (lang xa)) hoi. hieu van cau duc van hanh hai ((cua triet) OR (su triet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang x) or (lang xa)) hoi. hieu van cau duc van hanh hai ((cua triet) OR (su triet))*".