Perhaps you should try some spelling variations:
hieu cao » chieu cao, hieu cac, hieu ca
danh dai » danh dau, danh di, danh sai
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
nang xa » lang xa, nang ma, mang xa
truc va » thuc va, trung va
cua tre » cua te, cuu tre, cua triet

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 ky ((nang xa) OR (nang x)) hoi. hieu cao chat ((truc va) or (thuc vat)) danh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (nang x)) hoi. hieu cao chat ((truc va) OR (thuc vat)) danh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang xa) OR (nang x)) hoi. hieu cao chat ((truc va) or (thuc vat)) danh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) OR (nang x)) hoi. hieu cao chat ((truc va) or (thuc vat)) danh dai cua tre*.