Perhaps you should try some spelling variations:
thanh tai » thanh hai, thanh toan, doanh tai
nam thuc » nam thuoc, am thuc, nam thu
nang mai » nang tai, lang mai, nang cai
hanh tai » hang tai, han tai, hinh tai
te sach » toc sach
thuc xa » thuc xay, tuc xa, thuc va
cuc tre » duc tre, cua tre, cuu tre
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
va nam » van nam, ha nam, va nay

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky ((nang mai) OR (nang ma)) hoi. hieu va nam thuc xa ((hanh tai) or (thanh tai)) cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((nang mai) OR (nang ma)) hoi. hieu va nam thuc xa ((hanh tai) OR (thanh tai)) cuc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((nang mai) OR (nang ma)) hoi. hieu va nam thuc xa ((hanh tai) or (thanh tai)) cuc tre".
• Adding a wildcard symbol may retrieve word variants: te sach ky ((nang mai) OR (nang ma)) hoi. hieu va nam thuc xa ((hanh tai) or (thanh tai)) cuc tre*.