Perhaps you should try some spelling variations:
trinh vu » trinh ve, trinh vi, trinh su
trinh va » trinh van, trinh vat, trinh ve
cua tre » cua te, cua triet, dua tren
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
cuu tre » cau tren, cau treo
nam tu » nam thu, nam thuc
va nam » van nam, ha nam, va nay

You may be able to get more results by adjusting your search query.

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