Perhaps you should try some spelling variations:
tuyen tai » truyen tai, tuyen tap, nguyen tai
tien dung » tin dung, tieu dung, tien hung
xuyen tai » xuyen tac, nguyen tai, truyen tai
tac dung » sach dung, xay dung, tin dung
cac thu » cach thuc, cac thoi
va my » va may, va ky, va mo
va y » va ky, vat y, va ly

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tuyen tai) OR (xuyen tai)) cac thu đe co ban ((va y) or (va my)) ((tac dung) or (tien dung)) cong~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tuyen tai) OR (xuyen tai)) cac thu đe co ban ((va y) OR (va my)) ((tac dung) OR (tien dung)) cong.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tuyen tai) OR (xuyen tai)) cac thu đe co ban ((va y) or (va my)) ((tac dung) or (tien dung)) cong".
• Adding a wildcard symbol may retrieve word variants: ((tuyen tai) OR (xuyen tai)) cac thu đe co ban ((va y) or (va my)) ((tac dung) or (tien dung)) cong*.