Perhaps you should try some spelling variations:
khoan hoi » khoan nhoi, khoa hoi, khoa hoc
thu sach » tu sach, thuat sach, thuoc sach
van hanh » van thanh, ban hanh, van ban
ve triet » va trien, su triet
ky lang » ky dang, ky tang, tay lang
hieu ve » hieu va, hieu van
van anh » van thanh, tuan anh, van minh
ve nam » he nam, va nam, le nam
vai ve » va ve, dai ve, vai va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((ky lang) or (ky nang)) khoan hoi. hieu ve nam thu ((van hanh) or (van anh)) vai ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ky lang) OR (ky nang)) khoan hoi. hieu ve nam thu ((van hanh) OR (van anh)) vai ve triet.
• Adding a wildcard symbol may retrieve word variants: thu sach ((ky lang) or (ky nang)) khoan hoi. hieu ve nam thu ((van hanh) or (van anh)) vai ve triet*.