Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
hoc sach » hoc sinh, hoc cac, hoc anh
vu nang » vuc nang, va nang, vu dang
nang xa » nang x, lang xa, nang ma
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
vi cua » vai cua, di cua
va dao » ca dao
cua te » cua tu

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) or (hoc sach)) vu nang xa hoi. hieu ((va dau) OR (va dao)) thuc va hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (hoc sach)) vu nang xa hoi. hieu ((va dau) OR (va dao)) thuc va hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) or (hoc sach)) vu nang xa hoi. hieu ((va dau) OR (va dao)) thuc va hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (hoc sach)) vu nang xa hoi. hieu ((va dau) OR (va dao)) thuc va hanh vi cua te*.