Perhaps you should try some spelling variations:
ban benh » san benh, ba benh, ban banh
hieu van » hieu va, thien van, lieu va
cam duc » cam xuc, cao duc, pham duc
cua tre » cuu tre, cua triet, dua tren
benh di » benh dai, ben di, benh da
duc ban » duc tan, duc van, dua ban
van cam » van nam, van lam, van cau
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
sac ky » cac ky, sai ky
cua te » cua tu

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 ty) or (sac ky)) nang xa hoi. hieu van cam duc ban benh di ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ty) OR (sac ky)) nang xa hoi. hieu van cam duc ban benh di ((cua tre) OR (cua te))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ty) or (sac ky)) nang xa hoi. hieu van cam duc ban benh di ((cua tre) OR (cua te))*".