Perhaps you should try some spelling variations:
dang loai » dang hoai, dang loi, dung loai
thu sach » tu sach, thuat sach, thuoc sach
dan loai » phan loai, nhan loai, dang hoai
thuc day » thuc dan, thuc vat
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan
sach ky » sac ky, sach y, sach ty
ve nam » he nam, va nam, le nam
ca tre » ca tren, cua tre, ca tru
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang x hoi. hieu ve nam ((thuc va) or (thuc day)) ((dang loai) OR (dan loai)) ca tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang x hoi. hieu ve nam ((thuc va) OR (thuc day)) ((dang loai) OR (dan loai)) ca tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang x hoi. hieu ve nam ((thuc va) or (thuc day)) ((dang loai) OR (dan loai)) ca tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang x hoi. hieu ve nam ((thuc va) or (thuc day)) ((dang loai) OR (dan loai)) ca tre*.