Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
nuoc van » nuoc va, nuoc san, luoc van
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
hieu va » lieu va, hieu qua
cua tre » cuu tre, cua triet, dua tren
tu sach » thu sach, te sach, tu cach
lang ha » long ha
ky lang » ky nang, ky dang, ky tang
su sach » so sach, vu sach
ha hoi » hoa hoi, ha noi, xa hoi
cua te » cua tu

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)) ky lang ha hoi. hieu va cac nuoc van hanh vi ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky lang ha hoi. hieu va cac nuoc van hanh vi ((cua tre) OR (cua te))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky lang ha hoi. hieu va cac nuoc van hanh vi ((cua tre) OR (cua te))*".