Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
sach tu » sach thu, cach tu, sach uu
nang xa » nang x, lang xa, nang ma
sach ty » sach y, sach thu, xach tay
van cam » van nam, van lam, van cau
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, dua tren

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