Perhaps you should try some spelling variations:
so sach » so sanh, bo sach, co sach
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
thuc va » thuc vat, thuc dan, thuc day
van hau » van ha, van hai, van dau
van cau » van dau, van chat, toan cau
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach y ((nang xa) or (nang ma)) hoi. hieu ((van cau) OR (van hau)) thuc va danh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y ((nang xa) OR (nang ma)) hoi. hieu ((van cau) OR (van hau)) thuc va danh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach y ((nang xa) or (nang ma)) hoi. hieu ((van cau) OR (van hau)) thuc va danh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: so sach y ((nang xa) or (nang ma)) hoi. hieu ((van cau) OR (van hau)) thuc va danh vi cua tre*.