Perhaps you should try some spelling variations:
cau triet » cau trieu, su triet, cua triet
cau treo » cau theo, cau tren, cau trieu
manh hai » lanh hai, minh hai, thanh hai
hieu van » hieu va, thien van, lieu va
nang mai » nang ma, nang tai, lang mai
mai hoi » mai khoi, dai hoi, lai hoi
va manh » van manh, va danh, va hanh
so sach » so sanh, bo sach, co sach
su sach » vu sach
y nang » ky nang, ly nang, v nang
thu va » thuc va, thue va, tu va

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

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