Perhaps you should try some spelling variations:
sach doi » sach moi, sach dao, sach bai
sach hoi » sach moi, cach thoi, hoach hoi
cau thuc » cau truc, cuu thuc, can thuc
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
le cua » ly cua
ve cua » de cua, te cua, ve cum
va cau » van cau, va cac, va dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat ((sach hoi) OR (sach doi)) lang xa hoi. hieu va cau thuc dan hanh ((ve cua) or (le cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat ((sach hoi) OR (sach doi)) lang xa hoi. hieu va cau thuc dan hanh ((ve cua) OR (le cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat ((sach hoi) OR (sach doi)) lang xa hoi. hieu va cau thuc dan hanh ((ve cua) or (le cua)) te".
• Adding a wildcard symbol may retrieve word variants: thuat ((sach hoi) OR (sach doi)) lang xa hoi. hieu va cau thuc dan hanh ((ve cua) or (le cua)) te*.