Perhaps you should try some spelling variations:
sach truc » cach thuc, sach tren, sach thu
hanh lam » thanh lap, hanh kem, hanh va
va triet » va trien, ve triet, cua triet
thi hanh » thi thanh
dinh ve » dinh ket, dinh van
va dinh » van dinh, va kinh, va tinh
lam xuc » cam xuc, lam duoc
tu sach » thu sach, su sach, te sach
xuc va » duc va, tuc va, luc va
co hai » co dai, co hoi, o hai
o hoi » co hoi, o hoc, o hai
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach truc nano ((o hoi) or (co hai)). thi hanh lam xuc va dinh ve ((va triet) or (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach truc nano ((o hoi) OR (co hai)). thi hanh lam xuc va dinh ve ((va triet) OR (va thiet)).
• Adding a wildcard symbol may retrieve word variants: tu sach truc nano ((o hoi) or (co hai)). thi hanh lam xuc va dinh ve ((va triet) or (va thiet))*.