Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
van cam » van nam, van lam, van cau
cuu tre » cua tre, cau tren, cau treo
luc 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: tu sach ky nang xa hoi. hieu van cam ((luc va) OR (duc va)) hanh vi ((cuu tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. hieu van cam ((luc va) OR (duc va)) hanh vi ((cuu tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. hieu van cam ((luc va) OR (duc va)) hanh vi ((cuu tre) or (cua triet))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. hieu van cam ((luc va) OR (duc va)) hanh vi ((cuu tre) or (cua triet))*.