Perhaps you should try some spelling variations:
trinh dai » trinh tai, trinh di, trinh da
so sach » so sanh, bo sach, co sach
cao hoi » cau hoi, co hoi, cao hoc
hieu ve » hieu va, hieu van
xuc may » truc may, phuc may
cua tre » cuu tre, cua triet, dua tren
y nang » ky nang, ly nang, v nang
ve cac » va cac, vien cac
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: so sach y nang cao hoi. hieu ve cac ((xuc may) OR (xuc hay)) trinh dai ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y nang cao hoi. hieu ve cac ((xuc may) OR (xuc hay)) trinh dai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach y nang cao hoi. hieu ve cac ((xuc may) OR (xuc hay)) trinh dai ((cua tre) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: so sach y nang cao hoi. hieu ve cac ((xuc may) OR (xuc hay)) trinh dai ((cua tre) or (cua te))*.