Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
toc sach » doc sach, thuoc sach, nuoc sach
phan duc » pham duc, phan tu, phan dau
hoc sach » hoc sinh, hoc cac, hoc anh
tu cach » tu cac
duc van » duc va, duc tan, duc manh
ve phan » va phan, ke phan, ve phat
hieu ve » hieu va, hieu van
hang xa » hoang xa, hang va, hang ca
tu hang » thu hang, tu hanh, tu hung
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 (((toc sach) OR (hoc sach)))) tu hang xa hoi. hieu ve phan duc van hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (((toc sach) OR (hoc sach)))) tu hang xa hoi. hieu ve phan duc van hanh vi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (((toc sach) OR (hoc sach)))) tu hang xa hoi. hieu ve phan duc van hanh vi cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (((toc sach) OR (hoc sach)))) tu hang xa hoi. hieu ve phan duc van hanh vi cuu tre*.