Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
qua phan » cua phan, qua than, quang phan
phan luc » nhan luc, phan duc, phan suc
van hanh » van thanh, ban hanh, van anh
va trien » va truyen, va tuyen, va tieng
sach ky » sac ky, sach y, sach ty
luc van » luoc van, luu van, duc van
su hien » su kien, su tien, thu hien
nang o » nang co, nang ho, nang ro
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: thuat sach ky nang o hoi. hieu qua phan luc van hanh vi ((((va thiet) or (va trien))) or (su hien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky nang o hoi. hieu qua phan luc van hanh vi ((((va thiet) OR (va trien))) OR (su hien)).
• Adding a wildcard symbol may retrieve word variants: thuat sach ky nang o hoi. hieu qua phan luc van hanh vi ((((va thiet) or (va trien))) or (su hien))*.