Perhaps you should try some spelling variations:
dua tren » dung tren
van hanh » van thanh, ban hanh, van anh
tuan soc » quan so, xuan son, dan soc
hieu van » hieu va, thien van, lieu va
van tuan » van quan, van ban, anh tuan
tang van » dang van, hoang van, trong van
lang van » dang van, hoang van, giang van
soc van » hoc van, oc van, sac van
cuu tre » cua tre, cau tren, cau treo
bao ky » cao ky, ban ky, bac ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: te bao ky ((lang van) OR (tang van)) hoi. hieu van tuan soc van hanh vi ((cuu tre) or (dua tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te bao ky ((lang van) OR (tang van)) hoi. hieu van tuan soc van hanh vi ((cuu tre) OR (dua tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te bao ky ((lang van) OR (tang van)) hoi. hieu van tuan soc van hanh vi ((cuu tre) or (dua tren))".
• Adding a wildcard symbol may retrieve word variants: te bao ky ((lang van) OR (tang van)) hoi. hieu van tuan soc van hanh vi ((cuu tre) or (dua tren))*.