Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh tai » thanh tai, hang tai, han tai
cham duc » pham duc, cham soc, pham duy
tai cuu » tai cuc, tai buu, tai cua
va hanh » van hanh, va thanh, va danh
va cham » va chat, va tham
tu nano » truc nano
tu nang » tru nang, tu nong, tu lang
cuu tre » cua tre, cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) OR (toc sach)) ((tu nang) or (tu nano)) xa hoi. lieu va cham duc va hanh tai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ((tu nang) OR (tu nano)) xa hoi. lieu va cham duc va hanh tai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ((tu nang) or (tu nano)) xa hoi. lieu va cham duc va hanh tai cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) ((tu nang) or (tu nano)) xa hoi. lieu va cham duc va hanh tai cuu tre*.