Perhaps you should try some spelling variations:
su sach » so sach, vu sach
tu sach » thu sach, te sach, tu cach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
cua tre » cuu tre, cua triet, dua tren
cua te » cua tu

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