Perhaps you should try some spelling variations:
dat khanh » van khanh, duy khanh
cua viet » ca viet, hoa viet, cua vat
va triet » va thiet, va trien, ve triet
khanh vi » hanh vi, khanh v, nhanh vi
va pham » van pham, va phat, va phap
duc dat » duc duat, duoc dat, duc dai
sach ky » sac ky, sach y, sach kem
nang xa » nang x, lang xa, nang ma
sach ty » sach y, sach tu, sach thu
hieu va » lieu va, hieu qua

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 ky) or (sach ty)) nang xa hoi. hieu va pham duc dat khanh vi ((va triet) or (cua viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach ty)) nang xa hoi. hieu va pham duc dat khanh vi ((va triet) OR (cua viet)).
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach ty)) nang xa hoi. hieu va pham duc dat khanh vi ((va triet) or (cua viet))*.