Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
sach tay » xach tay, sach hay, sach nay
tay tang » tay lang, tay trung, tay quang
tang mai » tang ma, tang tai, lang mai
te sach » toc sach
mai hoi » mai khoi, dai hoi, lai hoi
hieu va » lieu va
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
cu tren » tu tren, dua tren
vi cu » vi su, vi xu, vi du

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 tay tang mai hoi. ((hieu va) or (hieu qua)) cham thuc va hanh vi cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach tay tang mai hoi. ((hieu va) OR (hieu qua)) cham thuc va hanh vi cu tren.
• Adding a wildcard symbol may retrieve word variants: te sach tay tang mai hoi. ((hieu va) or (hieu qua)) cham thuc va hanh vi cu tren*.