Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
thu sach » tu sach, thuat sach, thuoc sach
day hanh » day nhanh, day thanh, dao hanh
thuc day » thuc dan, thuc vat
ve pham » vi pham, v pham, ve phan
hieu ve » hieu va, hieu van
sach ky » sac ky, sach y, sach ty
hoi hoi » hoi hoc, hoc hoi, hoi doi
noi hoi » noi doi, doi hoi, noi hai
di cua » doi cua, de cua, do cua

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 ky nang ((noi hoi) OR (hoi hoi)). hieu ve pham thuc day hanh ((di cua) or (dai cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ((noi hoi) OR (hoi hoi)). hieu ve pham thuc day hanh ((di cua) OR (dai cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang ((noi hoi) OR (hoi hoi)). hieu ve pham thuc day hanh ((di cua) or (dai cua)) te".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ((noi hoi) OR (hoi hoi)). hieu ve pham thuc day hanh ((di cua) or (dai cua)) te*.