Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
thu sach » tu sach, thuat sach, thuoc sach
mai khoi » mai khoa, tai khoa, cac khoi
danh vai » danh sai, doanh van, dang van
cau tren » cu tren, dau tren, ca tren
mai hoi » dai hoi, lai hoi, mai doi
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
danh va » doanh va, hanh va, anh va
va nham » va cham, va tham, va nha
sach v » sach va, sach y, sach 2
v nang » va nang, vu nang, van nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach v nang ((mai hoi) or (mai khoi)). hieu va nham thuc va ((danh vai) OR (danh va)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach v nang ((mai hoi) OR (mai khoi)). hieu va nham thuc va ((danh vai) OR (danh va)) cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach v nang ((mai hoi) or (mai khoi)). hieu va nham thuc va ((danh vai) OR (danh va)) cau tren".
• Adding a wildcard symbol may retrieve word variants: thu sach v nang ((mai hoi) or (mai khoi)). hieu va nham thuc va ((danh vai) OR (danh va)) cau tren*.