Perhaps you should try some spelling variations:
nang mai » nang ma, nang tai, lang mai
va triet » va thiet, va trien, ve triet
tu sach » thu sach, su sach, te sach
sach tu » sach thu, cach tu, sach ty
tu nang » tru nang, tu nong, tu nano
mai hoi » mai khoi, dai hoi, lai hoi
cam duc » cam xuc, cao duc, nam duoc
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
di va » dai va, di vao, doi 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 tu nang mai hoi. hieu qua ((cam duc) or (pham duc)) va hanh di va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tu nang mai hoi. hieu qua ((cam duc) OR (pham duc)) va hanh di va triet.
• Adding a wildcard symbol may retrieve word variants: tu sach tu nang mai hoi. hieu qua ((cam duc) or (pham duc)) va hanh di va triet*.