Perhaps you should try some spelling variations:
cam thuc » am thuc, cam thu, can thuc
nam thuc » nam thuoc, am thuc, nam thu
nang ma » tang ma, sang ma, nang cao
va hanh » van hanh, va thanh, va danh
luu tre » luu tru, cuu tre, luy tre
su xac » pu xac
su cac » tu cac, su cao, su can
ma hoi » mai hoi, xa hoi, ma hoa
vi luu » vi lua

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

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