Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
sach thu » sach thue, sach tham, cach thuc
loai ca » loai cay, loai cua, loai va
ve nham » ve nha, ve cham
hieu ve » hieu va, hieu van
bang xa » lang xa, bang va, mang xa
va dan » va dao, va dau, va dap
ca dan » cac dan, ca dao
ca tre » ca tren, cua tre, ca tru

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

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