Perhaps you should try some spelling variations:
cua triet » su triet, va triet
cua viet » ca viet, hoa viet, cua vat
dau truc » cau truc, dai truc, doan truc
hanh lai » hanh lam, hanh tai, thanh lap
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
sach ty » sach tu, sach thu, xach tay
va dau » va dao

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 y) or (sach ty)) nang xa hoi. hieu va dau truc va hanh lai ((cua triet) OR (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach y) OR (sach ty)) nang xa hoi. hieu va dau truc va hanh lai ((cua triet) OR (cua viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach y) or (sach ty)) nang xa hoi. hieu va dau truc va hanh lai ((cua triet) OR (cua viet))".
• Adding a wildcard symbol may retrieve word variants: tu ((sach y) or (sach ty)) nang xa hoi. hieu va dau truc va hanh lai ((cua triet) OR (cua viet))*.