Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
tu cach » tu cac
tu hang » thu hang, tu hanh, tu hung
hang xa » hoang xa, hang va, hang ca
ve phan » va phan, ke phan, vi phan
ve phat » va phat, te phat, de phat
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren, cau treo
vi cuu » vi luu, vinh cuu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cach) or (doc sach)) tu hang xa hoi. hieu ((ve phan) or (ve phat)) duc va hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (doc sach)) tu hang xa hoi. hieu ((ve phan) OR (ve phat)) duc va hanh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (doc sach)) tu hang xa hoi. hieu ((ve phan) or (ve phat)) duc va hanh vi cuu tre*.