Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
ban hanh » ban hang
nang mai » nang ma, nang tai, lang mai
tu sach » thu sach, te sach, tu cach
mai hoi » mai khoi, dai hoi, lai hoi
su sach » so sach, vu sach
nam xuc » cam xuc, nam xua, nam thuc
y nang » ky nang, ly nang, v nang
vi cua » vai cua, di cua

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) OR (su sach)) y nang mai hoi. hieu van nam xuc ((ban hanh) or (va thanh)) vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) y nang mai hoi. hieu van nam xuc ((ban hanh) OR (va thanh)) vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (su sach)) y nang mai hoi. hieu van nam xuc ((ban hanh) or (va thanh)) vi cua triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (su sach)) y nang mai hoi. hieu van nam xuc ((ban hanh) or (va thanh)) vi cua triet*.