Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
chat cua » nhat cua, chat va, ca cua
van hanh » van thanh, ban hanh, van anh
chat huu » pham huu
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
sach tu » sach thu, cach tu, sach ty
hieu ve » hieu va, hieu van
nano xa » nano va, nano bac, nano cau
tu nano » truc nano

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach tu nano xa hoi. hieu ve ((chat cua) or (chat huu)) van hanh vi ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach tu nano xa hoi. hieu ve ((chat cua) OR (chat huu)) van hanh vi ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach tu nano xa hoi. hieu ve ((chat cua) or (chat huu)) van hanh vi ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: toc sach tu nano xa hoi. hieu ve ((chat cua) or (chat huu)) van hanh vi ((cua tre) OR (cuu tre))*.