Perhaps you should try some spelling variations:
thuoc sac » thuoc sach, thuoc dac, thuoc sai
dang xay » dang van, van xay
hieu van » hieu va, thien van, lieu va
cau treo » cau theo, cau tren, cau triet
nang xa » nang x, lang xa, nang ma
van cam » van nam, van lam, van cau
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren
sac ky » cac ky, sai ky
cam tu » cam thu, nam tu, dam tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sac ky ((nang xa) or (dang xay)) hoi. hieu van cam tu va hanh vi ((cuu tre) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sac ky ((nang xa) OR (dang xay)) hoi. hieu van cam tu va hanh vi ((cuu tre) OR (cau treo)).
• Adding a wildcard symbol may retrieve word variants: thuoc sac ky ((nang xa) or (dang xay)) hoi. hieu van cam tu va hanh vi ((cuu tre) or (cau treo))*.