Perhaps you should try some spelling variations:
cach thuc » anh thuc, cac thu
sach tham » sach nha
tai cua » thai cua, tai cuc, tri cua
han tai » hang tai, nhan tai, van tai
hieu va » lieu va, hieu qua
va han » va phan, van han, va hanh
nang o » nang co, nang ho, nang ro
cua tu » cua tuc, cua su, cua cu
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ((cach thuc) or (sach tham)) nang o hoi. hieu va ((nhan luc) or (nang luc)) va han tai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((cach thuc) OR (sach tham)) nang o hoi. hieu va ((nhan luc) OR (nang luc)) va han tai cua tu.
• Adding a wildcard symbol may retrieve word variants: te ((cach thuc) or (sach tham)) nang o hoi. hieu va ((nhan luc) or (nang luc)) va han tai cua tu*.