Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
hanh kien » danh kien, anh kien, thanh vien
tham xuc » tham nuoc, pham duc, cam xuc
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
sach tu » sach thu, cach tu, sach ty
tu nang » tru nang, tu nong, tu nano
nang ma » tang ma, sang ma, nang cao
kien su » nien su, tien su, vien sau
su viet » so viet
ma hoi » mai hoi, xa hoi, ma hoa

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 tu nang ma hoi. hieu qua ((tham xuc) or (tham thuc)) van hanh kien su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tu nang ma hoi. hieu qua ((tham xuc) OR (tham thuc)) van hanh kien su viet.
• Adding a wildcard symbol may retrieve word variants: tu sach tu nang ma hoi. hieu qua ((tham xuc) or (tham thuc)) van hanh kien su viet*.