Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
tham thuc » nham thuc, tam thuc, thai thuc
va triet » va thiet, va trien, ve triet
sach dao » lanh dao
hanh dao » lanh dao, thanh dat, thanh dam
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
tang ma » mang may, tang van
tang xa » trang xa, lang xa, tang ha
hieu ve » hieu va, hieu van
dao va » dao van, tao va, do va

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 dao ((tang xa) or (tang ma)) hoi. hieu ve ((tham thuc) or (pham thuc)) va hanh dao va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach dao ((tang xa) OR (tang ma)) hoi. hieu ve ((tham thuc) OR (pham thuc)) va hanh dao va triet.
• Adding a wildcard symbol may retrieve word variants: tu sach dao ((tang xa) or (tang ma)) hoi. hieu ve ((tham thuc) or (pham thuc)) va hanh dao va triet*.