Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
nang mai » nang ma, nang tai, lang mai
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, ban thanh, va tinh
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
van cac » van hac, van cau, van bac
cac day » cac dan, cac dai, cac cay
su tien » su kien, su hien, tu tieng
y nang » ky nang, ly nang, v nang

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 y nang mai hoi. hieu van cac day va thanh san ((cua triet) or (su tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang mai hoi. hieu van cac day va thanh san ((cua triet) OR (su tien)).
• Adding a wildcard symbol may retrieve word variants: tu sach y nang mai hoi. hieu van cac day va thanh san ((cua triet) or (su tien))*.