Perhaps you should try some spelling variations:
su sach » so sach, vu sach
sach tu » sach thu, cach tu, sach ty
va hanh » van hanh, va thanh, va danh
nay tuc » nay tu, cay thuc, day thuc
cuu tre » cua tre, cau tren, cau treo
tu nang » tru nang, tu nong, tu nano
co hoi » co hoc, co loi
va nay » va ngay, va cay
tuc va » thuc va, truc va, tuc xa
vi cuu » vi luu, vinh cuu
o hoc » co hoc, mo hoc, so hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach tu nang ((((co hoi) or (o hoc))) or (xa hoi)). lieu va nay tuc va hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach tu nang ((((co hoi) OR (o hoc))) OR (xa hoi)). lieu va nay tuc va hanh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: su sach tu nang ((((co hoi) or (o hoc))) or (xa hoi)). lieu va nay tuc va hanh vi cuu tre*.