Perhaps you should try some spelling variations:
nha thuoc » nha nuoc, nhan thuc, nha hoc
thuoc vat » thuc vat, thuoc va, thuoc bat
nang mai » nang ma, nang tai, lang mai
vat hanh » vat thanh, van hanh, va hanh
sach ky » sach y, sach ty, sach kem
mai hoi » mai khoi, dai hoi, lai hoi
hieu va » lieu va, hieu qua
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
va nha » va nho, ve nha
di cua » dai cua, doi cua, de cua

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 ky) or (sac ky)) nang mai hoi. hieu va nha thuoc vat hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sac ky)) nang mai hoi. hieu va nha thuoc vat hanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) or (sac ky)) nang mai hoi. hieu va nha thuoc vat hanh di cua tre*.