Perhaps you should try some spelling variations:
thien van » thi van
ban thanh » ban hanh, ban hang
thanh ca » thanh cha, thanh cac, thanh ha
cau tren » cu tren, dau tren, ca tren
sach ky » sach y, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
thu ban » thu hang
cuu tre » cua tre, cau treo
sac ky » cac ky, sai ky

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 ky) OR (sac ky)) nang xa hoi. thien van nam thu ban thanh ca ((cuu tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((sach ky) OR (sac ky)) nang xa hoi. thien van nam thu ban thanh ca ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "so ((sach ky) OR (sac ky)) nang xa hoi. thien van nam thu ban thanh ca ((cuu tre) or (cau tren))".
• Adding a wildcard symbol may retrieve word variants: so ((sach ky) OR (sac ky)) nang xa hoi. thien van nam thu ban thanh ca ((cuu tre) or (cau tren))*.