Perhaps you should try some spelling variations:
cam thuc » am thuc, nam thuc, cam thu
thanh ve » hanh ve, thanh va, thanh vien
sach thu » sach thue, sach thieu, sach tham
lang van » dang van, tang van, hoang van
thanh de » hanh de, thanh do, thanh le
thuc ban » thuoc ban, thuc dan, thu ban
hieu ve » hieu va, hieu van
sach ty » sach y, sach tu, xach tay
van hoi » van hoa, van hoc, van hoe
ve cam » ve cham, ve cac, 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: tu ((sach ty) or (sach thu)) lang van hoi. hieu ve cam thuc ban ((thanh de) OR (thanh ve)) cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach thu)) lang van hoi. hieu ve cam thuc ban ((thanh de) OR (thanh ve)) cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sach thu)) lang van hoi. hieu ve cam thuc ban ((thanh de) OR (thanh ve)) cua vat".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach thu)) lang van hoi. hieu ve cam thuc ban ((thanh de) OR (thanh ve)) cua vat*.