Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hieu van » hieu va, thien van, lieu va
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
cau tren » cu tren, dau tren, ca tren
nang xa » nang x, lang xa, nang ma
van cac » van hac, van cau, van bac
y nang » ky nang, ly nang, v nang
va dan » ca dan, va dao, va dau
dan di » danh di, dan da, dan de
di cau » da cau, diem cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y nang xa hoi. hieu van cac nuoc va dan di cau tren~.
• Adding a wildcard symbol may retrieve word variants: toc sach y nang xa hoi. hieu van cac nuoc va dan di cau tren*.