Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
nang mai » nang ma, nang tai, lang mai
van hanh » van thanh, ban hanh, van anh
sach uu » sach luu, sach tu, sach xu
mai hoi » mai khoi, dai hoi, lai hoi
sach vu » sach va, sach tu, sach xu
hieu va » lieu va, hieu qua
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
hanh ki » hanh vi, hanh ky, hanh kien
va cam » va cham, va cac, va cao
ki su » ky su

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 vu) or (sach uu)) nang mai hoi. hieu va cam duc van hanh ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach vu) OR (sach uu)) nang mai hoi. hieu va cam duc van hanh ki su triet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach vu) or (sach uu)) nang mai hoi. hieu va cam duc van hanh ki su triet*.