Perhaps you should try some spelling variations:
nang mai » nang ma, nang tai, lang mai
cam truc » nam truc, lam truoc, nam truoc
hanh vai » hanh vi, hanh va, hanh tai
mai hoi » mai khoi, dai hoi, lai hoi
va hanh » van hanh, va thanh, va danh
vai hoa » van hoa, va hoa, dai hoa
sach v » sach va, sach 2, sach vay

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

• Performing a fuzzy search may retrieve terms with similar spellings: so ((sach v) OR (sach y)) nang mai hoi. hieu qua ((cam truc) or (cau truc)) va hanh vai hoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((sach v) OR (sach y)) nang mai hoi. hieu qua ((cam truc) OR (cau truc)) va hanh vai hoa viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so ((sach v) OR (sach y)) nang mai hoi. hieu qua ((cam truc) or (cau truc)) va hanh vai hoa viet".
• Adding a wildcard symbol may retrieve word variants: so ((sach v) OR (sach y)) nang mai hoi. hieu qua ((cam truc) or (cau truc)) va hanh vai hoa viet*.