Perhaps you should try some spelling variations:
nhanh thuc » nhan thuc, thanh thuy, anh thuc
hanh truc » hang truc, hanh thuoc, hanh phuc
cuu tre » cua tre, cau tren, cau treo
va hanh » van hanh, va thanh, va danh
hieu va » lieu va, hieu qua
mang xa » lang xa, mang may, dang xay
nang ma » tang ma, sang ma, nang cao
sac ky » cac ky, sai ky
vi cuu » vi luu, vinh cuu
su sac » su sach, su cac, su xac

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ky ((mang xa) or (nang ma)) hoi. hieu va ((hanh truc) OR (nhanh thuc)) va hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky ((mang xa) OR (nang ma)) hoi. hieu va ((hanh truc) OR (nhanh thuc)) va hanh vi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sac ky ((mang xa) or (nang ma)) hoi. hieu va ((hanh truc) OR (nhanh thuc)) va hanh vi cuu tre".
• Adding a wildcard symbol may retrieve word variants: su sac ky ((mang xa) or (nang ma)) hoi. hieu va ((hanh truc) OR (nhanh thuc)) va hanh vi cuu tre*.