Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
va thanh » gia thanh, ban thanh, va tinh
te sach » toc sach
sach lo » sach dao, sach doi, sach hoi
va hanh » van hanh, va danh, ban hanh
hieu va » lieu va, hieu qua
lo nang » ho nang, ly nang, loai nang
va nam » van nam, ha nam, va nay
x hoi » xa hoi, o hoi, x ho
di su » doi su, da su, de su
ki su » ky su

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach lo nang x hoi. hieu va nam thuc ((va hanh) or (va thanh)) ((di su) OR (ki su)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach lo nang x hoi. hieu va nam thuc ((va hanh) OR (va thanh)) ((di su) OR (ki su)) viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach lo nang x hoi. hieu va nam thuc ((va hanh) or (va thanh)) ((di su) OR (ki su)) viet".
• Adding a wildcard symbol may retrieve word variants: te sach lo nang x hoi. hieu va nam thuc ((va hanh) or (va thanh)) ((di su) OR (ki su)) viet*.