Perhaps you should try some spelling variations:
hanh than » hanh han, hanh nhan, hanh phan
nang ban » hang ban, nang quan, nang sang
nang cap » nang cao, nang cham, nang phap
su triet » su viet, su tien, ve triet
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
than su » nhan su, tan su, than so
va cam » va cham, va cac, va cao
cam tu » cam thu, nam tu, dam tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky ((nang ban) or (nang cap)) hoi. hieu va cam tu va hanh than su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky ((nang ban) OR (nang cap)) hoi. hieu va cam tu va hanh than su triet.
• Adding a wildcard symbol may retrieve word variants: vu sach ky ((nang ban) or (nang cap)) hoi. hieu va cam tu va hanh than su triet*.