Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hanh tai » thanh tai, hang tai, han tai
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
vu cham » va cham, vu kham, tu cham
ve cham » va cham, ve chat, ve chim
su tien » su kien, su hien, tu tieng
ve cam » ve cac, va cam, ve cai
nang o » nang co, nang ho, nang ro
tai su » tai so, tai tu, lai su
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ky nang o hoi. hieu ((ve cam) or (((ve cham) OR (vu cham)))) thuc va hanh tai su tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ky nang o hoi. hieu ((ve cam) OR (((ve cham) OR (vu cham)))) thuc va hanh tai su tien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ky nang o hoi. hieu ((ve cam) or (((ve cham) OR (vu cham)))) thuc va hanh tai su tien".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ky nang o hoi. hieu ((ve cam) or (((ve cham) OR (vu cham)))) thuc va hanh tai su tien*.