Perhaps you should try some spelling variations:
manh hanh » xanh hanh, danh thanh, minh thanh
duc manh » suc manh, duc anh, duc minh
tu sach » thu sach, te sach, tu cach
hanh ki » hanh vi, hanh ky, hanh kien
ve cham » va cham, ve chat, vu cham
su viet » so viet
nang ma » tang ma, sang ma, nang cao
su sach » so sach, vu sach
v nang » va nang, vu nang, van nang
ve cai » va cai, ve cac, ve tai
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) OR (su sach)) v nang ma hoa. hieu ((ve cai) or (ve cham)) duc manh hanh ki su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) v nang ma hoa. hieu ((ve cai) OR (ve cham)) duc manh hanh ki su viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (su sach)) v nang ma hoa. hieu ((ve cai) or (ve cham)) duc manh hanh ki su viet*".