Perhaps you should try some spelling variations:
hanh tai » thanh tai, hang tai, han tai
su triet » su viet, su tien, ve triet
nang xa » nang x, lang xa, nang ma
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
sac ky » cac ky
va nam » ha nam, va nay
tai su » tai so, tai tu, lai su

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

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