Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
cau tren » cu tren, dau tren, ca tren
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
sach ty » sach y, sach thu, xach tay
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
sach tu » sach thu, cach tu, sach uu
ve cac » va cac, vien cac
ky va » ly va, ke va, my va

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

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