Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sach truc » cach thuc, sach tren, sach thu
hac truc » hoc truc, hang truc, cau truc
su sach » so sach, vu sach
co sach » bo sach, cuon sach, hoc sach
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
y nang » ky nang, ly nang, v nang
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: ((su sach) or (co sach)) y nang x ho. hieu va ((hac truc) OR (sach truc)) va hanh vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (co sach)) y nang x ho. hieu va ((hac truc) OR (sach truc)) va hanh vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (co sach)) y nang x ho. hieu va ((hac truc) OR (sach truc)) va hanh vi cua triet".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (co sach)) y nang x ho. hieu va ((hac truc) OR (sach truc)) va hanh vi cua triet*.