Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
hanh tai » thanh tai, hang tai, han tai
cham tuc » nham thuc, pham thuc, tham thuc
sach tai » sach bai, sach tham, sach dao
cau tren » cu tren, dau tren, ca tren
tai hang » thai hang, thi hang, tai lang
hieu ve » hieu va, hieu van
xa hanh » xa thanh, xa khanh, va hanh
cua tre » cua te, cuu tre, cua triet
ve cham » va cham, ve chat, vu cham
va hoa » van hoa, va hoc, ma hoa
va hoi » xa hoi, va hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach tai hang ((va hoi) or (va hoa)). hieu ve cham tuc xa hanh tai ((cua tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach tai hang ((va hoi) OR (va hoa)). hieu ve cham tuc xa hanh tai ((cua tre) OR (cau tren)).
• Adding a wildcard symbol may retrieve word variants: hoc sach tai hang ((va hoi) or (va hoa)). hieu ve cham tuc xa hanh tai ((cua tre) or (cau tren))*.