Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
dinh lam » dinh van, tinh lao
lam chat » luan chat, cao chat, ly chat
chat tre » chay tren, chat tai, cho tre
nang xa » nang x, lang xa, nang ma
ve pham » vi pham, ve phan, ve phat
va dinh » van dinh, va kinh, va tinh
v pham » vi pham, d pham

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)) ky nang xa hoi. hieu ((ve pham) OR (v pham)) duc va dinh lam chat tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky nang xa hoi. hieu ((ve pham) OR (v pham)) duc va dinh lam chat tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) ky nang xa hoi. hieu ((ve pham) OR (v pham)) duc va dinh lam chat tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ky nang xa hoi. hieu ((ve pham) OR (v pham)) duc va dinh lam chat tre*.