Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
toc sach » hoc sach, doc sach, nuoc sach
cam thuc » am thuc, nam thuc, cam thu
cao hoi » co hoi, cao hoc, tao hoi
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
luu tre » luu tru, cuu tre, luy tre
y nang » ky nang, ly nang, v nang
ve cam » ve cham, ve cac, va cam
vi luu » vi lua

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)) y nang ((cao hoi) or (cau hoi)). hieu ve cam thuc va hanh vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thuoc sach)) y nang ((cao hoi) OR (cau hoi)). hieu ve cam thuc va hanh vi luu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (thuoc sach)) y nang ((cao hoi) or (cau hoi)). hieu ve cam thuc va hanh vi luu tre*".