Perhaps you should try some spelling variations:
trinh viet » ninh viet, trinh vat
va trinh » van trinh, va tinh, lap trinh
viet cua » viec cua, viet ca, viet qua
te sach » toc sach
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, me hoi
ve cac » vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty xang ((ma hoi) or (ma hoa)). hieu ((ve cac) OR (va cac)) duc va trinh viet cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty xang ((ma hoi) OR (ma hoa)). hieu ((ve cac) OR (va cac)) duc va trinh viet cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty xang ((ma hoi) or (ma hoa)). hieu ((ve cac) OR (va cac)) duc va trinh viet cua tre*".