Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
nham thuc » nhan thuc, nam thuc, nham thu
toc sach » hoc sach, doc sach, nuoc sach
van nang » van quang, van ban, van dong
hieu van » hieu va, thien van, lieu va
van nham » van nam, van nhan, van tham
hanh doi » thanh doi, hanh noi, hang doi
cau tren » cu tren, dau tren, ca tren
cao hoi » cau hoi, co hoi, cao hoc
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
doi cau » doi dau, di cau, doi ca

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) OR (thuoc sach)) van nang cao hoi. hieu van nham thuc va hanh doi cau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (thuoc sach)) van nang cao hoi. hieu van nham thuc va hanh doi cau tren".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (thuoc sach)) van nang cao hoi. hieu van nham thuc va hanh doi cau tren*.