Perhaps you should try some spelling variations:
trinh tai » trinh toan, trinh tu, trinh han
thu sach » tu sach, thuat sach, thuoc sach
va trinh » van trinh, va tinh, lap trinh
tang mam » dang mam, mang mam, tang dam
ve chat » va chat, van chat
ve cham » va cham, vu cham, ve chim
sach ky » sac ky, sach y, sach ty
tang ma » mang may, tang van
cuc tre » duc tre, cua tre, cuu tre

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky ((tang ma) or (tang mam)) hoi. hieu ((ve cham) OR (ve chat)) duc va trinh tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky ((tang ma) OR (tang mam)) hoi. hieu ((ve cham) OR (ve chat)) duc va trinh tai cuc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky ((tang ma) or (tang mam)) hoi. hieu ((ve cham) OR (ve chat)) duc va trinh tai cuc tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ky ((tang ma) or (tang mam)) hoi. hieu ((ve cham) OR (ve chat)) duc va trinh tai cuc tre*.