Perhaps you should try some spelling variations:
nang hoat » nang hoa, trang hoat, hang hoa
cua viet » ca viet, hoa viet, cua vat
thuc day » thuc dan, thuc vat
hoat hoi » hoat doi, hoa hoi, hoat ho
vanh dai » van dai, vanh tai, lanh dao
hanh dai » hanh tai, hanh dao, thanh dat
te sach » toc sach
hieu he » hieu ve, hiem he, hieu le
thuc va » thuc vat, thuc dan
y nang » ky nang, ly nang, v nang
he nam » ha nam, nghe nam

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y nang hoat hoi. hieu he nam ((thuc va) OR (thuc day)) ((hanh dai) OR (vanh dai)) cua viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y nang hoat hoi. hieu he nam ((thuc va) or (thuc day)) ((hanh dai) OR (vanh dai)) cua viet~".
• Adding a wildcard symbol may retrieve word variants: te sach y nang hoat hoi. hieu he nam ((thuc va) or (thuc day)) ((hanh dai) OR (vanh dai)) cua viet*.