Perhaps you should try some spelling variations:
trinh vi » trinh va, trinh ve, trinh viet
tu sach » thu sach, te sach, tu cach
cam duc » cam xuc, cao duc, pham duc
tinh vi » tinh voi, tinh va, dinh vi
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
su sach » so sach, vu sach
va cam » va cham, va cac, va cao
x hoi » xa hoi, o hoi, x ho

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