Perhaps you should try some spelling variations:
sach kem » hanh kem
van hanh » van thanh, ban hanh, van anh
hanh tue » hanh tu, hanh tuyen, hanh theo
hieu va » lieu va, hieu qua
nam xuc » cam xuc, nam xua, nam thuc
xuc van » duc van, luc van, vuc van
tue cua » te cua
cua tre » cua te, cuu tre, cua triet
sai ky » sac ky
va nam » van nam, ha nam, va nay
x hoi » xa hoi, o hoi, x ho

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 kem) or (sai ky)) nang x hoi. hieu va nam xuc van hanh tue cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach kem) OR (sai ky)) nang x hoi. hieu va nam xuc van hanh tue cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach kem) or (sai ky)) nang x hoi. hieu va nam xuc van hanh tue cua tre*.