Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
thuc dan » thuc hanh, hoc dan, thuc vat
cau treo » cau theo, cau tren, cau triet
lang ha » long ha
lang xa » dang xay, lang van
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc day
dan van » dang van, doan van, dao van
van cau » van dau, van hau, van chat
va am » va lam, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky ((lang xa) or (lang ha)) hoi. lieu va am ((thuc va) OR (thuc dan)) dan van cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky ((lang xa) OR (lang ha)) hoi. lieu va am ((thuc va) OR (thuc dan)) dan van cau treo*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky ((lang xa) or (lang ha)) hoi. lieu va am ((thuc va) OR (thuc dan)) dan van cau treo*".