Perhaps you should try some spelling variations:
dan thanh » dang thanh, danh thanh, ban thanh
thanh vi » hanh vi, thanh va, thanh ve
thuc dan » thuc hanh, hoc dan, thuc vat
cac thuc » cach thuc, cac thu, can thuc
qua cac » cua cac
nang co » nang cao, nang doc, nang noi
nang ra » nang ma, lang ra, nang ro
cua tu » cua tuc, cua su, cua te
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
cua cu » cua chu, cua cau, cua su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky ((nang co) or (nang ra)) hoi. hieu qua cac thuc dan thanh vi ((cua tu) or (cua cu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang co) OR (nang ra)) hoi. hieu qua cac thuc dan thanh vi ((cua tu) OR (cua cu)).
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang co) or (nang ra)) hoi. hieu qua cac thuc dan thanh vi ((cua tu) or (cua cu))*.