Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
sai ky » sac ky
ve cam » ve cham, ve cac, va cam
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 ty) or (sai ky)) nang xa hoi. hieu ve cam thuc va hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sai ky)) nang xa hoi. hieu ve cam thuc va hanh di cua tre.
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sai ky)) nang xa hoi. hieu ve cam thuc va hanh di cua tre*.