Perhaps you should try some spelling variations:
duc tuan » duc thuan, duc tan, duc toan
dang xa » dang xay, lang xa, dang ha
hieu va » lieu va, hieu qua
cam duc » cam xuc, cao duc, pham duc
anh thi » anh tho, dinh thi, dang thi
cuc tre » duc tre, cuu tre, cuc thue
cua tre » cua te, cuu tre, cua triet
dai ky » dan ky, sai ky
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((dai ky) or (dai ly)) dang xa hoi. hieu va cam duc tuan anh thi ((cuc tre) OR (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((dai ky) OR (dai ly)) dang xa hoi. hieu va cam duc tuan anh thi ((cuc tre) OR (cua tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((dai ky) or (dai ly)) dang xa hoi. hieu va cam duc tuan anh thi ((cuc tre) OR (cua tre))".
• Adding a wildcard symbol may retrieve word variants: su ((dai ky) or (dai ly)) dang xa hoi. hieu va cam duc tuan anh thi ((cuc tre) OR (cua tre))*.