Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
ban thanh » ban hanh, ban hang
duc ban » duc tan, duc van, dua ban
cam duc » cam xuc, cao duc, pham duc
qua cam » qua cham, qua cac, qua ca
lang xa » lang ha, dang xay, lang van
tang ma » mang may, tang van
sach tu » sach thu, cach tu, sach ty
cu tren » tu tren, dua tren
tai cu » tai cuc, tai cua, tai co

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 y) or (sach tu)) ((tang ma) or (lang xa)) hoi. hieu qua cam duc ban thanh tai cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach y) OR (sach tu)) ((tang ma) OR (lang xa)) hoi. hieu qua cam duc ban thanh tai cu tren.
• Adding a wildcard symbol may retrieve word variants: tu ((sach y) or (sach tu)) ((tang ma) or (lang xa)) hoi. hieu qua cam duc ban thanh tai cu tren*.