Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
su sach » so sach, vu sach
sach tu » sach thu, cach tu, sach ty
tu nang » tru nang, tu nong, tu nano
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, dua tren
ve cam » ve cham, ve cac, va cam
luc va » duc va, tuc va, loc 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 tu nang xa hoi. hieu ve cam ((luc va) or (tuc xa)) hanh vi ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach tu nang xa hoi. hieu ve cam ((luc va) OR (tuc xa)) hanh vi ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach tu nang xa hoi. hieu ve cam ((luc va) or (tuc xa)) hanh vi ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: su sach tu nang xa hoi. hieu ve cam ((luc va) or (tuc xa)) hanh vi ((cua tre) OR (cua triet))*.