Perhaps you should try some spelling variations:
sach thi » sach thu, sach tai, sach thieu
thi sang » thi nang, thi hang, thi song
sang cho » danh cho, dung cho, sang tao
te sach » toc sach
cua cau » cua cac, cua cay, cua can
dao van » do van, dang van
dac van » cac van, dam van, duc van
hieu ve » hieu va, hieu van
cho hoc » co hoc, khoa hoc
cua chu » sua chua
ve cac » va cac, vien cac

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: te sach thi sang cho hoc. hieu ve cac ((dac van) OR (dao van)) hanh vi ((cua cau) OR (cua chu))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach thi sang cho hoc. hieu ve cac ((dac van) OR (dao van)) hanh vi ((cua cau) or (cua chu))~".
• Adding a wildcard symbol may retrieve word variants: te sach thi sang cho hoc. hieu ve cac ((dac van) OR (dao van)) hanh vi ((cua cau) or (cua chu))*.