Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van thanh » ban thanh, van tuan
thanh vi » hanh vi, thanh va, thanh ve
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
nang xa » lang xa, nang ma, mang xa
ve cac » va cac, vien cac
bo van » vo van, so van, do van
vi cua » vai cua, di cua

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