Perhaps you should try some spelling variations:
sach tru » sach truc, sach thu, sach tu
tru nang » tra nang, tri nang, truc nano
toc cham » toc thai
van hanh » van thanh, ban hanh, van anh
ve triet » va trien, su triet
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
tu cham » thi cham
va hanh » va thanh, va danh, ban hanh

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 tru nang xa hoi. hieu ((tu cham) or (toc cham)) duc ((va hanh) OR (van hanh)) de ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tru nang xa hoi. hieu ((tu cham) OR (toc cham)) duc ((va hanh) OR (van hanh)) de ve triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach tru nang xa hoi. hieu ((tu cham) or (toc cham)) duc ((va hanh) OR (van hanh)) de ve triet*".