Perhaps you should try some spelling variations:
trinh viet » ninh viet, trinh vat
trinh vi » trinh va, trinh ve, trinh van
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
dang xa » dang xay, lang xa, dang ha
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
va coc » va cuoc, va cac, va hoc
luc va » tuc va, loc va

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