Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
cam truc » nam truc, lam truoc, nam truoc
so sanh » do sanh
nang ma » tang ma, sang ma, nang cao
va hanh » van hanh, va thanh, va danh
so sach » bo sach, co sach, hoc sach
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
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: ((so sach) OR (so sanh)) y nang ma hoi. hieu qua ((cam truc) or (cau truc)) va hanh vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (so sanh)) y nang ma hoi. hieu qua ((cam truc) OR (cau truc)) va hanh vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) OR (so sanh)) y nang ma hoi. hieu qua ((cam truc) or (cau truc)) va hanh vi su triet".
• Adding a wildcard symbol may retrieve word variants: ((so sach) OR (so sanh)) y nang ma hoi. hieu qua ((cam truc) or (cau truc)) va hanh vi su triet*.