Perhaps you should try some spelling variations:
nhan thuc » nhan luc, dan thuc, toan thuc
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 ve » hieu va, hieu van
ve nhan » ve nha, de nhan, va nhan
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
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 ve nhan thuc 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 ve nhan thuc vat hanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) or (sac ky)) nang mai hoi. hieu ve nhan thuc vat hanh di cua tre*.