Perhaps you should try some spelling variations:
cac thuc » cach thuc, cac thu, can thuc
thuc day » thuc dan, thuc vat
dang xay » dang van
day hanh » day nhanh, day thanh, dao hanh
sach phu » sach thu, sach phat, sach thue
cua tre » cua te, cua triet, dua tren
hanh va » hang va, hanh vi
te sach » toc sach
hieu va » lieu va, hieu qua
cuu tre » cau tren, cau treo

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 phu ((dang xay) OR (van xay)) hoi. hieu va cac thuc day hanh va ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach phu ((dang xay) OR (van xay)) hoi. hieu va cac thuc day hanh va ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach phu ((dang xay) OR (van xay)) hoi. hieu va cac thuc day hanh va ((cua tre) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: te sach phu ((dang xay) OR (van xay)) hoi. hieu va cac thuc day hanh va ((cua tre) or (cuu tre))*.