Perhaps you should try some spelling variations:
thuoc van » thuc van, thuoc ban, thuoc tan
thuoc va » thuc va, thuoc ma, thuong va
dang xay » dang van, van xay
cua tre » cua te, cuu tre, cua triet
nang xa » nang x, lang xa, nang ma
hanh va » hang va, hanh vi
hieu le » hieu ve, hieu he, hieu ly
va cua » va chua, via cua, ca cua
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
le nam » ly nam, he nam, le na

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 xa) or (dang xay)) hoi. hieu le nam ((thuoc van) OR (thuoc va)) hanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang xa) OR (dang xay)) hoi. hieu le nam ((thuoc van) OR (thuoc va)) hanh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky ((nang xa) or (dang xay)) hoi. hieu le nam ((thuoc van) OR (thuoc va)) hanh va cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang xa) or (dang xay)) hoi. hieu le nam ((thuoc van) OR (thuoc va)) hanh va cua tre*.