Perhaps you should try some spelling variations:
toc sach » thuoc sach, nuoc sach, toc san
doc sach » nuoc sach, dac sac, bo sach
hoc sach » hoc sinh, hoc cac, hoc anh
cau thuc » cau truc, cuu thuc, can thuc
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
v nang » va nang, vu nang, van nang
va cau » van cau, va cac, va dau
vi cua » vai cua, di cua
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 (doc sach))) or (hoc sach)) v nang xa hoi. hieu va cau thuc va hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((((toc sach) OR (doc sach))) OR (hoc sach)) v nang xa hoi. hieu va cau thuc va hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((toc sach) OR (doc sach))) or (hoc sach)) v nang xa hoi. hieu va cau thuc va hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: ((((toc sach) OR (doc sach))) or (hoc sach)) v nang xa hoi. hieu va cau thuc va hanh vi cua te*.