Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
cham duc » pham duc, cham soc, pham duy
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
duc van » duc va, duc tan, duc manh
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, dua tren

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