Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
tu sach » thu sach, su sach, te sach
va hanh » van hanh, va thanh, va danh
y nang » ky nang, ly nang, v nang
ve cam » ve cham, va cam, ve cai
ve cac » va cac, vien cac
xuc va » duc va, tuc va, luc va
x hoi » xa hoi, o hoi, 5 hoi
vi su » va su, ve su, ki su

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 y nang ((x hoi) OR (x ho)). hieu ((ve cam) or (ve cac)) xuc va hanh vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang ((x hoi) OR (x ho)). hieu ((ve cam) OR (ve cac)) xuc va hanh vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang ((x hoi) OR (x ho)). hieu ((ve cam) or (ve cac)) xuc va hanh vi su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang ((x hoi) OR (x ho)). hieu ((ve cam) or (ve cac)) xuc va hanh vi su triet*.