Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
cua triet » cua viet, su triet, va triet
vat phan » va phan, van phan, sat phan
phan lap » phan dau
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang ho » nang hoc, nang co, tang ho
hieu vu » hieu va, hieu su, dieu vu
hieu ve » hieu va, hieu van
lap cua » lai cua, tap cua, lam cua
ho hoi » hoc hoi, hoa hoi, hoi hoi

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 ty nang ho hoi. ((hieu vu) or (hieu ve)) cham thuc vat phan lap cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ho hoi. ((hieu vu) OR (hieu ve)) cham thuc vat phan lap cua triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ho hoi. ((hieu vu) or (hieu ve)) cham thuc vat phan lap cua triet*.